diff --git a/src/crypto/cfb.js b/src/crypto/cfb.js
index 87e3dbcf..41e871cb 100644
--- a/src/crypto/cfb.js
+++ b/src/crypto/cfb.js
@@ -181,7 +181,7 @@ export default {
     cipherfn = new cipher[cipherfn](key);
     const block_size = cipherfn.blockSize;
 
-    let iblock = new Uint8Array(block_size);
+    const iblock = new Uint8Array(block_size);
     let ablock = new Uint8Array(block_size);
 
     let i;
@@ -189,30 +189,10 @@ export default {
     let n;
     let text = new Uint8Array(ciphertext.length - block_size);
 
-    // initialisation vector
-    for (i = 0; i < block_size; i++) {
-      iblock[i] = 0;
-    }
-
-    iblock = cipherfn.encrypt(iblock);
-    for (i = 0; i < block_size; i++) {
-      ablock[i] = ciphertext[i];
-      iblock[i] ^= ablock[i];
-    }
-
-    ablock = cipherfn.encrypt(ablock);
-
-    // test check octets
-    if (iblock[block_size - 2] !== (ablock[0] ^ ciphertext[block_size]) ||
-        iblock[block_size - 1] !== (ablock[1] ^ ciphertext[block_size + 1])) {
-      throw new Error('CFB decrypt: invalid key');
-    }
-
     /*  RFC4880: Tag 18 and Resync:
      *  [...] Unlike the Symmetrically Encrypted Data Packet, no
      *  special CFB resynchronization is done after encrypting this prefix
      *  data.  See "OpenPGP CFB Mode" below for more details.
-
      */
 
     j = 0;
diff --git a/src/crypto/cmac.js b/src/crypto/cmac.js
index b6d31ec7..d3675fbd 100644
--- a/src/crypto/cmac.js
+++ b/src/crypto/cmac.js
@@ -48,7 +48,7 @@ function rightXorMut(data, padding) {
 
 function pad(data, padding, padding2) {
   // if |M| in {n, 2n, 3n, ...}
-  if (data.length % blockLength === 0) {
+  if (data.length && data.length % blockLength === 0) {
     // then return M xor→ B,
     return rightXorMut(data, padding);
   }
diff --git a/src/crypto/public_key/elliptic/curves.js b/src/crypto/public_key/elliptic/curves.js
index f19f6662..2186ea9c 100644
--- a/src/crypto/public_key/elliptic/curves.js
+++ b/src/crypto/public_key/elliptic/curves.js
@@ -177,7 +177,14 @@ Curve.prototype.keyFromSecret = function (secret) { // Only for ed25519
 };
 
 Curve.prototype.keyFromPublic = function (pub) {
-  return new KeyPair(this, { pub: pub });
+  const keyPair = new KeyPair(this, { pub: pub });
+  if (
+    this.keyType === enums.publicKey.ecdsa &&
+    keyPair.keyPair.validate().result !== true
+  ) {
+    throw new Error('Invalid elliptic public key');
+  }
+  return keyPair;
 };
 
 Curve.prototype.genKeyPair = async function () {
diff --git a/src/key.js b/src/key.js
index b43450df..7b98420f 100644
--- a/src/key.js
+++ b/src/key.js
@@ -1451,6 +1451,19 @@ async function wrapKeyObject(secretKeyPacket, secretSubkeyPackets, options) {
   packetlist.push(secretKeyPacket);
 
   await Promise.all(options.userIds.map(async function(userId, index) {
+    function createdPreferredAlgos(algos, configAlgo) {
+      if (configAlgo) { // Not `uncompressed` / `plaintext`
+        const configIndex = algos.indexOf(configAlgo);
+        if (configIndex >= 1) { // If it is included and not in first place,
+          algos.splice(configIndex, 1); // remove it.
+        }
+        if (configIndex !== 0) { // If it was included and not in first place, or wasn't included,
+          algos.unshift(configAlgo); // add it to the front.
+        }
+      }
+      return algos;
+    }
+
     const userIdPacket = new packet.Userid();
     userIdPacket.format(userId);
 
@@ -1462,26 +1475,30 @@ async function wrapKeyObject(secretKeyPacket, secretSubkeyPackets, options) {
     signaturePacket.publicKeyAlgorithm = secretKeyPacket.algorithm;
     signaturePacket.hashAlgorithm = await getPreferredHashAlgo(null, secretKeyPacket);
     signaturePacket.keyFlags = [enums.keyFlags.certify_keys | enums.keyFlags.sign_data];
-    signaturePacket.preferredSymmetricAlgorithms = [];
-    // prefer aes256, aes128, then aes192 (no WebCrypto support: https://www.chromium.org/blink/webcrypto#TOC-AES-support)
-    signaturePacket.preferredSymmetricAlgorithms.push(enums.symmetric.aes256);
-    signaturePacket.preferredSymmetricAlgorithms.push(enums.symmetric.aes128);
-    signaturePacket.preferredSymmetricAlgorithms.push(enums.symmetric.aes192);
-    signaturePacket.preferredSymmetricAlgorithms.push(enums.symmetric.cast5);
-    signaturePacket.preferredSymmetricAlgorithms.push(enums.symmetric.tripledes);
+    signaturePacket.preferredSymmetricAlgorithms = createdPreferredAlgos([
+      // prefer aes256, aes128, then aes192 (no WebCrypto support: https://www.chromium.org/blink/webcrypto#TOC-AES-support)
+      enums.symmetric.aes256,
+      enums.symmetric.aes128,
+      enums.symmetric.aes192,
+      enums.symmetric.cast5,
+      enums.symmetric.tripledes
+    ], config.encryption_cipher);
     if (config.aead_protect && config.aead_protect_version === 4) {
-      signaturePacket.preferredAeadAlgorithms = [];
-      signaturePacket.preferredAeadAlgorithms.push(enums.aead.eax);
-      signaturePacket.preferredAeadAlgorithms.push(enums.aead.ocb);
+      signaturePacket.preferredAeadAlgorithms = createdPreferredAlgos([
+        enums.aead.eax,
+        enums.aead.ocb
+      ], config.aead_mode);
     }
-    signaturePacket.preferredHashAlgorithms = [];
-    // prefer fast asm.js implementations (SHA-256). SHA-1 will not be secure much longer...move to bottom of list
-    signaturePacket.preferredHashAlgorithms.push(enums.hash.sha256);
-    signaturePacket.preferredHashAlgorithms.push(enums.hash.sha512);
-    signaturePacket.preferredHashAlgorithms.push(enums.hash.sha1);
-    signaturePacket.preferredCompressionAlgorithms = [];
-    signaturePacket.preferredCompressionAlgorithms.push(enums.compression.zlib);
-    signaturePacket.preferredCompressionAlgorithms.push(enums.compression.zip);
+    signaturePacket.preferredHashAlgorithms = createdPreferredAlgos([
+      // prefer fast asm.js implementations (SHA-256). SHA-1 will not be secure much longer...move to bottom of list
+      enums.hash.sha256,
+      enums.hash.sha512,
+      enums.hash.sha1
+    ], config.prefer_hash_algorithm);
+    signaturePacket.preferredCompressionAlgorithms = createdPreferredAlgos([
+      enums.compression.zlib,
+      enums.compression.zip
+    ], config.compression);
     if (index === 0) {
       signaturePacket.isPrimaryUserID = true;
     }
@@ -1690,7 +1707,7 @@ export async function getPreferredHashAlgo(key, keyPacket, date=new Date(), user
  */
 export async function getPreferredAlgo(type, keys, date=new Date(), userId={}) {
   const prefProperty = type === 'symmetric' ? 'preferredSymmetricAlgorithms' : 'preferredAeadAlgorithms';
-  const defaultAlgo = type === 'symmetric' ? config.encryption_cipher : config.aead_mode;
+  const defaultAlgo = type === 'symmetric' ? enums.symmetric.aes128 : enums.aead.eax;
   const prioMap = {};
   await Promise.all(keys.map(async function(key) {
     const primaryUser = await key.getPrimaryUser(date, userId);
diff --git a/src/message.js b/src/message.js
index d8818616..5bdff7ca 100644
--- a/src/message.js
+++ b/src/message.js
@@ -153,6 +153,7 @@ Message.prototype.decrypt = async function(privateKeys, passwords, sessionKeys,
 Message.prototype.decryptSessionKeys = async function(privateKeys, passwords) {
   let keyPackets = [];
 
+  let exception;
   if (passwords) {
     const symESKeyPacketlist = this.packets.filterByTag(enums.packet.symEncryptedSessionKey);
     if (!symESKeyPacketlist) {
@@ -181,23 +182,36 @@ Message.prototype.decryptSessionKeys = async function(privateKeys, passwords) {
       throw new Error('No public key encrypted session key packet found.');
     }
     await Promise.all(pkESKeyPacketlist.map(async function(keyPacket) {
-      const privateKeyPackets = new packet.List();
-      privateKeys.forEach(privateKey => {
-        privateKeyPackets.concat(privateKey.getKeys(keyPacket.publicKeyId).map(key => key.keyPacket));
-      });
-      await Promise.all(privateKeyPackets.map(async function(privateKeyPacket) {
-        if (!privateKeyPacket) {
-         return;
-        }
-        if (!privateKeyPacket.isDecrypted()) {
-          throw new Error('Private key is not decrypted.');
-        }
-        try {
-          await keyPacket.decrypt(privateKeyPacket);
-          keyPackets.push(keyPacket);
-        } catch (err) {
-          util.print_debug_error(err);
+      await Promise.all(privateKeys.map(async function(privateKey) {
+        const primaryUser = await privateKey.getPrimaryUser(); // TODO: Pass userId from somewhere.
+        let algos = [
+          enums.symmetric.aes256, // Old OpenPGP.js default fallback
+          enums.symmetric.aes128, // RFC4880bis fallback
+          enums.symmetric.tripledes // RFC4880 fallback
+        ];
+        if (primaryUser && primaryUser.selfCertification.preferredSymmetricAlgorithms) {
+          algos = algos.concat(primaryUser.selfCertification.preferredSymmetricAlgorithms);
         }
+
+        const privateKeyPackets = privateKey.getKeys(keyPacket.publicKeyId).map(key => key.keyPacket);
+        await Promise.all(privateKeyPackets.map(async function(privateKeyPacket) {
+          if (!privateKeyPacket) {
+            return;
+          }
+          if (!privateKeyPacket.isDecrypted()) {
+            throw new Error('Private key is not decrypted.');
+          }
+          try {
+            await keyPacket.decrypt(privateKeyPacket);
+            if (!algos.includes(enums.write(enums.symmetric, keyPacket.sessionKeyAlgorithm))) {
+              throw new Error('A non-preferred symmetric algorithm was used.');
+            }
+            keyPackets.push(keyPacket);
+          } catch (err) {
+            util.print_debug_error(err);
+            exception = err;
+          }
+        }));
       }));
       stream.cancel(keyPacket.encrypted); // Don't keep copy of encrypted data in memory.
       keyPacket.encrypted = null;
@@ -222,7 +236,7 @@ Message.prototype.decryptSessionKeys = async function(privateKeys, passwords) {
 
     return keyPackets.map(packet => ({ data: packet.sessionKey, algorithm: packet.sessionKeyAlgorithm }));
   }
-  throw new Error('Session key decryption failed.');
+  throw exception || new Error('Session key decryption failed.');
 };
 
 /**
@@ -230,7 +244,8 @@ Message.prototype.decryptSessionKeys = async function(privateKeys, passwords) {
  * @returns {(Uint8Array|null)} literal body of the message as Uint8Array
  */
 Message.prototype.getLiteralData = function() {
-  const literal = this.packets.findPacket(enums.packet.literal);
+  const msg = this.unwrapCompressed();
+  const literal = msg.packets.findPacket(enums.packet.literal);
   return (literal && literal.getBytes()) || null;
 };
 
@@ -239,7 +254,8 @@ Message.prototype.getLiteralData = function() {
  * @returns {(String|null)} filename of literal data packet as string
  */
 Message.prototype.getFilename = function() {
-  const literal = this.packets.findPacket(enums.packet.literal);
+  const msg = this.unwrapCompressed();
+  const literal = msg.packets.findPacket(enums.packet.literal);
   return (literal && literal.getFilename()) || null;
 };
 
@@ -248,7 +264,8 @@ Message.prototype.getFilename = function() {
  * @returns {(String|null)} literal body of the message interpreted as text
  */
 Message.prototype.getText = function() {
-  const literal = this.packets.findPacket(enums.packet.literal);
+  const msg = this.unwrapCompressed();
+  const literal = msg.packets.findPacket(enums.packet.literal);
   if (literal) {
     return literal.getText();
   }
diff --git a/src/packet/packetlist.js b/src/packet/packetlist.js
index b56c2cd2..03f8c7da 100644
--- a/src/packet/packetlist.js
+++ b/src/packet/packetlist.js
@@ -168,24 +168,10 @@ List.prototype.filterByTag = function (...args) {
 /**
  * Traverses packet tree and returns first matching packet
  * @param  {module:enums.packet} type The packet type
- * @returns {module:packet/packet|null}
+ * @returns {module:packet/packet|undefined}
  */
 List.prototype.findPacket = function (type) {
-  const packetlist = this.filterByTag(type);
-  if (packetlist.length) {
-    return packetlist[0];
-  }
-  let found = null;
-  for (let i = 0; i < this.length; i++) {
-    if (this[i].packets.length) {
-      found = this[i].packets.findPacket(type);
-      if (found) {
-        return found;
-      }
-    }
-  }
-
-  return null;
+  return this.find(packet => packet.tag === type);
 };
 
 /**
diff --git a/src/packet/public_key.js b/src/packet/public_key.js
index ca43ea05..2d6c6895 100644
--- a/src/packet/public_key.js
+++ b/src/packet/public_key.js
@@ -62,6 +62,11 @@ function PublicKey(date=new Date()) {
    * @type {Date}
    */
   this.created = util.normalizeDate(date);
+  /**
+   * Public key algorithm.
+   * @type {String}
+   */
+  this.algorithm = null;
   /**
    * Algorithm specific params
    * @type {Array<Object>}
diff --git a/src/packet/public_key_encrypted_session_key.js b/src/packet/public_key_encrypted_session_key.js
index 260497da..fc93e430 100644
--- a/src/packet/public_key_encrypted_session_key.js
+++ b/src/packet/public_key_encrypted_session_key.js
@@ -52,7 +52,10 @@ function PublicKeyEncryptedSessionKey() {
   this.version = 3;
 
   this.publicKeyId = new type_keyid();
+  this.publicKeyAlgorithm = null;
+
   this.sessionKey = null;
+  this.sessionKeyAlgorithm = null;
 
   /** @type {Array<module:type/mpi>} */
   this.encrypted = [];
@@ -150,7 +153,7 @@ PublicKeyEncryptedSessionKey.prototype.decrypt = async function (key) {
   key = util.str_to_Uint8Array(decoded.substring(1, decoded.length - 2));
 
   if (!util.equalsUint8Array(checksum, util.write_checksum(key))) {
-    throw new Error('Checksum mismatch');
+    throw new Error('Decryption error');
   } else {
     this.sessionKey = key;
     this.sessionKeyAlgorithm = enums.read(enums.symmetric, decoded.charCodeAt(0));
diff --git a/src/packet/signature.js b/src/packet/signature.js
index 0faf2875..bd78c8f3 100644
--- a/src/packet/signature.js
+++ b/src/packet/signature.js
@@ -666,6 +666,10 @@ Signature.prototype.verify = async function (key, signatureType, data) {
   const publicKeyAlgorithm = enums.write(enums.publicKey, this.publicKeyAlgorithm);
   const hashAlgorithm = enums.write(enums.hash, this.hashAlgorithm);
 
+  if (publicKeyAlgorithm !== enums.write(enums.publicKey, key.algorithm)) {
+    throw new Error('Public key algorithm used to sign signature does not match issuer key algorithm.');
+  }
+
   let toHash;
   let hash;
   if (this.hashed) {
diff --git a/test/crypto/elliptic.js b/test/crypto/elliptic.js
index 9e1b72c8..f4852b89 100644
--- a/test/crypto/elliptic.js
+++ b/test/crypto/elliptic.js
@@ -223,7 +223,17 @@ describe('Elliptic Curve Cryptography', async function () {
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
     ]);
-    const secp256k1_dummy_point = new Uint8Array([
+    const secp256k1_point = new Uint8Array([
+      0x04,
+      0x79, 0xBE, 0x66, 0x7E, 0xF9, 0xDC, 0xBB, 0xAC,
+      0x55, 0xA0, 0x62, 0x95, 0xCE, 0x87, 0x0B, 0x07,
+      0x02, 0x9B, 0xFC, 0xDB, 0x2D, 0xCE, 0x28, 0xD9,
+      0x59, 0xF2, 0x81, 0x5B, 0x16, 0xF8, 0x17, 0x98,
+      0x48, 0x3A, 0xDA, 0x77, 0x26, 0xA3, 0xC4, 0x65,
+      0x5D, 0xA4, 0xFB, 0xFC, 0x0E, 0x11, 0x08, 0xA8,
+      0xFD, 0x17, 0xB4, 0x48, 0xA6, 0x85, 0x54, 0x19,
+      0x9C, 0x47, 0xD0, 0x8F, 0xFB, 0x10, 0xD4, 0xB8]);
+    const secp256k1_invalid_point = new Uint8Array([
       0x04,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -233,7 +243,7 @@ describe('Elliptic Curve Cryptography', async function () {
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]);
-    const secp256k1_invalid_point = new Uint8Array([
+    const secp256k1_invalid_point_format = new Uint8Array([
       0x04,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -255,13 +265,18 @@ describe('Elliptic Curve Cryptography', async function () {
           'secp256k1', 8, [], [], [], []
         )).to.be.rejectedWith(Error, /Unknown point format/),
         expect(verify_signature(
-          'secp256k1', 8, [], [], [], secp256k1_invalid_point
+          'secp256k1', 8, [], [], [], secp256k1_invalid_point_format
         )).to.be.rejectedWith(Error, /Unknown point format/)
       ]);
     });
+    it('Invalid point', function (done) {
+      expect(verify_signature(
+        'secp256k1', 8, [], [], [], secp256k1_invalid_point
+      )).to.be.rejectedWith(Error, /Invalid elliptic public key/).notify(done);
+    });
     it('Invalid signature', function (done) {
       expect(verify_signature(
-        'secp256k1', 8, [], [], [], secp256k1_dummy_point
+        'secp256k1', 8, [], [], [], secp256k1_point
       )).to.eventually.be.false.notify(done);
     });
 
@@ -331,11 +346,21 @@ describe('Elliptic Curve Cryptography', async function () {
     ]);
     const secp256k1_point = new Uint8Array([
       0x04,
-      0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x79, 0xBE, 0x66, 0x7E, 0xF9, 0xDC, 0xBB, 0xAC,
+      0x55, 0xA0, 0x62, 0x95, 0xCE, 0x87, 0x0B, 0x07,
+      0x02, 0x9B, 0xFC, 0xDB, 0x2D, 0xCE, 0x28, 0xD9,
+      0x59, 0xF2, 0x81, 0x5B, 0x16, 0xF8, 0x17, 0x98,
+      0x48, 0x3A, 0xDA, 0x77, 0x26, 0xA3, 0xC4, 0x65,
+      0x5D, 0xA4, 0xFB, 0xFC, 0x0E, 0x11, 0x08, 0xA8,
+      0xFD, 0x17, 0xB4, 0x48, 0xA6, 0x85, 0x54, 0x19,
+      0x9C, 0x47, 0xD0, 0x8F, 0xFB, 0x10, 0xD4, 0xB8]);
+    const secp256k1_invalid_point = new Uint8Array([
+      0x04,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]);
@@ -354,6 +379,11 @@ describe('Elliptic Curve Cryptography', async function () {
         'secp256k1', 2, 7, [], [], [], []
       )).to.be.rejectedWith(Error, /Unknown point format/).notify(done);
     });
+    it('Invalid elliptic public key', function (done) {
+      expect(decrypt_message(
+        'secp256k1', 2, 7, secp256k1_value, secp256k1_invalid_point, secp256k1_data, []
+      )).to.be.rejectedWith(Error, /Invalid elliptic public key/).notify(done);
+    });
     it('Invalid key data integrity', function (done) {
       expect(decrypt_message(
         'secp256k1', 2, 7, secp256k1_value, secp256k1_point, secp256k1_data, []
diff --git a/test/general/key.js b/test/general/key.js
index a2ce51a3..bc84ba4f 100644
--- a/test/general/key.js
+++ b/test/general/key.js
@@ -1357,6 +1357,49 @@ function versionSpecificTests() {
     });
   });
 
+  it('Preferences of generated key - with config values', async function() {
+    const encryption_cipherVal = openpgp.config.encryption_cipher;
+    const prefer_hash_algorithmVal = openpgp.config.prefer_hash_algorithm;
+    const compressionVal = openpgp.config.compression;
+    const aead_modeVal = openpgp.config.aead_mode;
+    openpgp.config.encryption_cipher = openpgp.enums.symmetric.aes192;
+    openpgp.config.prefer_hash_algorithm = openpgp.enums.hash.sha384;
+    openpgp.config.compression = openpgp.enums.compression.zlib;
+    openpgp.config.aead_mode = openpgp.enums.aead.experimental_gcm;
+
+    const testPref = function(key) {
+      // key flags
+      const keyFlags = openpgp.enums.keyFlags;
+      expect(key.users[0].selfCertifications[0].keyFlags[0] & keyFlags.certify_keys).to.equal(keyFlags.certify_keys);
+      expect(key.users[0].selfCertifications[0].keyFlags[0] & keyFlags.sign_data).to.equal(keyFlags.sign_data);
+      expect(key.subKeys[0].bindingSignatures[0].keyFlags[0] & keyFlags.encrypt_communication).to.equal(keyFlags.encrypt_communication);
+      expect(key.subKeys[0].bindingSignatures[0].keyFlags[0] & keyFlags.encrypt_storage).to.equal(keyFlags.encrypt_storage);
+      const sym = openpgp.enums.symmetric;
+      expect(key.users[0].selfCertifications[0].preferredSymmetricAlgorithms).to.eql([sym.aes192, sym.aes256, sym.aes128, sym.cast5, sym.tripledes]);
+      if (openpgp.config.aead_protect && openpgp.config.aead_protect_version === 4) {
+        const aead = openpgp.enums.aead;
+        expect(key.users[0].selfCertifications[0].preferredAeadAlgorithms).to.eql([aead.experimental_gcm, aead.eax, aead.ocb]);
+      }
+      const hash = openpgp.enums.hash;
+      expect(key.users[0].selfCertifications[0].preferredHashAlgorithms).to.eql([hash.sha384, hash.sha256, hash.sha512, hash.sha1]);
+      const compr = openpgp.enums.compression;
+      expect(key.users[0].selfCertifications[0].preferredCompressionAlgorithms).to.eql([compr.zlib, compr.zip]);
+      expect(key.users[0].selfCertifications[0].features).to.eql(openpgp.config.aead_protect && openpgp.config.aead_protect_version === 4 ? [7] : [1]);
+    };
+    const opt = {numBits: 512, userIds: 'test <a@b.com>', passphrase: 'hello'};
+    if (openpgp.util.getWebCryptoAll()) { opt.numBits = 2048; } // webkit webcrypto accepts minimum 2048 bit keys
+    try {
+      const key = await openpgp.generateKey(opt);
+      testPref(key.key);
+      testPref((await openpgp.key.readArmored(key.publicKeyArmored)).keys[0]);
+    } finally {
+      openpgp.config.encryption_cipher = encryption_cipherVal;
+      openpgp.config.prefer_hash_algorithm = prefer_hash_algorithmVal;
+      openpgp.config.compression = compressionVal;
+      openpgp.config.aead_mode = aead_modeVal;
+    }
+  });
+
   it('Generated key is not unlocked by default', function() {
     const opt = {numBits: 512, userIds: 'test <a@b.com>', passphrase: '123'};
     if (openpgp.util.getWebCryptoAll()) { opt.numBits = 2048; } // webkit webcrypto accepts minimum 2048 bit keys
@@ -2147,14 +2190,14 @@ describe('Key', function() {
     expect(prefAlgo).to.equal(openpgp.enums.symmetric.aes256);
   });
 
-  it("getPreferredAlgo('symmetric') - two key - AES128", async function() {
+  it("getPreferredAlgo('symmetric') - two key - AES192", async function() {
     const keys = (await openpgp.key.readArmored(twoKeys)).keys;
     const key1 = keys[0];
     const key2 = keys[1];
     const primaryUser = await key2.getPrimaryUser();
-    primaryUser.selfCertification.preferredSymmetricAlgorithms = [6,7,3];
+    primaryUser.selfCertification.preferredSymmetricAlgorithms = [6,8,3];
     const prefAlgo = await openpgp.key.getPreferredAlgo('symmetric', [key1, key2]);
-    expect(prefAlgo).to.equal(openpgp.enums.symmetric.aes128);
+    expect(prefAlgo).to.equal(openpgp.enums.symmetric.aes192);
   });
 
   it("getPreferredAlgo('symmetric') - two key - one without pref", async function() {
@@ -2164,7 +2207,7 @@ describe('Key', function() {
     const primaryUser = await key2.getPrimaryUser();
     primaryUser.selfCertification.preferredSymmetricAlgorithms = null;
     const prefAlgo = await openpgp.key.getPreferredAlgo('symmetric', [key1, key2]);
-    expect(prefAlgo).to.equal(openpgp.config.encryption_cipher);
+    expect(prefAlgo).to.equal(openpgp.enums.symmetric.aes128);
   });
 
   it("getPreferredAlgo('aead') - one key - OCB", async function() {
@@ -2188,7 +2231,7 @@ describe('Key', function() {
     const primaryUser2 = await key2.getPrimaryUser();
     primaryUser2.selfCertification.features = [7]; // Monkey-patch AEAD feature flag
     const prefAlgo = await openpgp.key.getPreferredAlgo('aead', [key1, key2]);
-    expect(prefAlgo).to.equal(openpgp.config.aead_mode);
+    expect(prefAlgo).to.equal(openpgp.enums.aead.eax);
     const supported = await openpgp.key.isAeadSupported([key1, key2]);
     expect(supported).to.be.true;
   });
@@ -2201,7 +2244,7 @@ describe('Key', function() {
     primaryUser.selfCertification.features = [7]; // Monkey-patch AEAD feature flag
     primaryUser.selfCertification.preferredAeadAlgorithms = [2,1];
     const prefAlgo = await openpgp.key.getPreferredAlgo('aead', [key1, key2]);
-    expect(prefAlgo).to.equal(openpgp.config.aead_mode);
+    expect(prefAlgo).to.equal(openpgp.enums.aead.eax);
     const supported = await openpgp.key.isAeadSupported([key1, key2]);
     expect(supported).to.be.false;
   });
diff --git a/test/security/index.js b/test/security/index.js
index 5ca983e1..d515963f 100644
--- a/test/security/index.js
+++ b/test/security/index.js
@@ -2,4 +2,5 @@ describe('Security', function () {
   require('./message_signature_bypass');
   require('./unsigned_subpackets');
   require('./subkey_trust');
+  require('./preferred_algo_mismatch');
 });
diff --git a/test/security/preferred_algo_mismatch.js b/test/security/preferred_algo_mismatch.js
new file mode 100644
index 00000000..74cb644d
--- /dev/null
+++ b/test/security/preferred_algo_mismatch.js
@@ -0,0 +1,49 @@
+const openpgp = typeof window !== 'undefined' && window.openpgp ? window.openpgp : require('../../dist/openpgp');
+
+const { key, cleartext, enums, packet: { List, Signature } } = openpgp;
+
+const chai = require('chai');
+chai.use(require('chai-as-promised'));
+
+const expect = chai.expect;
+
+const messageArmor = `-----BEGIN PGP MESSAGE-----
+Version: OpenPGP.js VERSION
+Comment: https://openpgpjs.org
+
+wYwD3eCUoDfD5yoBA/4rhxaaw+E2ma+LdmLVDBRqxglhIgnM6EgNxzf8J5Ty
+ecQBLOf3BjjC72mJ9RqMmvQ16aG4EXXDAUmCP1sBLj+b7V1t4keeyTn+2nXu
+7Wgu2yq9CvZahRLsayt3y8VodZwTi3K/+gmx1f8EhdLPONQgGkYAqZ3Tyyd0
+KF3pknplvdI+AXqRs0n2vVr89oIdmQPJFSHEoJtltbSNxhwShdzDvOor2FKJ
+vhGWNysion2aBg0fIbgDUKeXKp8YN44LDTk=
+=RYrv
+-----END PGP MESSAGE-----`;
+
+const privateKeyArmor = `-----BEGIN PGP PRIVATE KEY BLOCK-----
+Version: OpenPGP.js VERSION
+Comment: https://openpgpjs.org
+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+=oopr
+-----END PGP PRIVATE KEY BLOCK-----`;
+
+it('Does not accept message encrypted with algo not mentioned in preferred algorithms', async function() {
+  const message = await openpgp.message.readArmored(messageArmor);
+  const privKey = (await openpgp.key.readArmored(privateKeyArmor)).keys[0];
+  await expect(openpgp.decrypt({ message, privateKeys: [privKey] })).to.be.rejectedWith('A non-preferred symmetric algorithm was used.');
+});