/ 
CryptX-0.014
/ Crypt::PK::ECC
Security Advisories (6)
CVE-2025-40912 (2025-06-11)

CryptX for Perl before version 0.065 contains a dependency that may be susceptible to malformed unicode. CryptX embeds the tomcrypt library. The versions of that library in CryptX before 0.065 may be susceptible to CVE-2019-17362.

CVE-2025-40914 (2025-06-11)

Perl CryptX before version 0.087 contains a dependency that may be susceptible to an integer overflow. CryptX embeds a version of the libtommath library that is susceptible to an integer overflow associated with CVE-2023-36328.

CVE-2026-41564 (2026-04-23)

CryptX versions before 0.088 for Perl do not reseed the Crypt::PK PRNG state after forking. The Crypt::PK::RSA, Crypt::PK::DSA, Crypt::PK::DH, Crypt::PK::ECC, Crypt::PK::Ed25519 and Crypt::PK::X25519 modules seed a per-object PRNG state in their constructors and reuse it without fork detection. A Crypt::PK::* object created before `fork()` shares byte-identical PRNG state with every child process, and any randomized operation they perform can produce identical output, including key generation. Two ECDSA or DSA signatures from different processes are enough to recover the signing private key through nonce-reuse key recovery. This affects preforking services such as the Starman web server, where a Crypt::PK::* object loaded at startup is inherited by every worker process.

CVE-2018-25099 (2018-10-26)

A user can pass anything as the tag into gcm_decrypt_verify() and it will return decrypted plaintext.

CVE-2026-41565 (2026-05-28)

CryptX versions before 0.088_001 for Perl have a stack buffer overflow in four AEAD decrypt_verify helpers. The gcm_decrypt_verify, ccm_decrypt_verify, chacha20poly1305_decrypt_verify and eax_decrypt_verify XS routines copied the caller-supplied authentication tag into a fixed 144-byte stack buffer (MAXBLOCKSIZE) without checking the supplied length. A longer tag overwrites the stack past the buffer. Version 0.088 added the clamp to gcm_decrypt_verify, and 0.088_001 added it to the other three. Any caller of an affected helper that forwards an attacker-controlled tag longer than the buffer can trigger the overflow.

CVE-2026-13758 (2026-06-29)

CryptX versions before 0.088_001 for Perl compare AEAD authentication tags in non-constant time in the streaming decrypt_done path. The decrypt_done($tag) form compares it against the computed tag with memNE (memcmp() != 0), which short-circuits on the first differing byte, so its run time depends on the number of matching leading bytes. This affects all five AEAD modes: GCM, CCM, ChaCha20Poly1305, EAX and OCB. The one-shot *_decrypt_verify helpers are unaffected; they verify the tag inside libtomcrypt with a constant-time comparison. The timing difference is a tag-verification oracle. An attacker who can submit many candidate tags for the same nonce, ciphertext and associated data while measuring the timing precisely enough may recover the expected tag byte by byte and forge a message that verifies.

NAME

Crypt::PK::ECC - Public key cryptography based on EC

SYNOPSIS

### OO interface

#Encryption: Alice
my $pub = Crypt::PK::ECC->new('Bob_pub_ecc1.der'); 
my $ct = $pub->encrypt("secret message");
#
#Encryption: Bob (received ciphertext $ct)
my $priv = Crypt::PK::ECC->new('Bob_priv_ecc1.der');
my $pt = $priv->decrypt($ct);
 
#Signature: Alice
my $priv = Crypt::PK::ECC->new('Alice_priv_ecc1.der');
my $sig = $priv->sign_message($message);
#
#Signature: Bob (received $message + $sig)
my $pub = Crypt::PK::ECC->new('Alice_pub_ecc1.der');
$pub->verify_message($sig, $message) or die "ERROR";

#Shared secret
my $priv = Crypt::PK::ECC->new('Alice_priv_ecc1.der');
my $pub = Crypt::PK::ECC->new('Bob_pub_ecc1.der'); 
my $shared_secret = $priv->shared_secret($pub);

#Key generation
my $pk = Crypt::PK::ECC->new();
$pk->generate_key(24);
my $private_der = $pk->export_key_der('private');
my $public_der = $pk->export_key_der('public');
my $public_ansi_x963 = $pk->export_key_x963();

### Functional interface

#Encryption: Alice
my $ct = ecc_encrypt('Bob_pub_ecc1.der', "secret message");
#Encryption: Bob (received ciphertext $ct)
my $pt = ecc_decrypt('Bob_priv_ecc1.der', $ct);
 
#Signature: Alice
my $sig = ecc_sign_message('Alice_priv_ecc1.der', $message);
#Signature: Bob (received $message + $sig)
ecc_verify_message('Alice_pub_ecc1.der', $sig, $message) or die "ERROR";

#Shared secret
my $shared_secret = ecc_shared_secret('Alice_priv_ecc1.der', 'Bob_pub_ecc1.der');

DESCRIPTION

The module provides a set of core ECC functions as well that are designed to be the Elliptic Curve analogy of all of the Diffie-Hellman routines (ECDH).

FUNCTIONS

ecc_encrypt

Elliptic Curve Diffie-Hellman (ECDH) encryption.

ECCDH Encryption is performed by producing a random key, hashing it, and XOR'ing the digest against the plaintext. See method "encrypt" below.

my $ct = ecc_encrypt($pub_key_filename, $message);
#or
my $ct = ecc_encrypt(\$buffer_containing_pub_key, $message);

ecc_decrypt

Elliptic Curve Diffie-Hellman (ECDH) decryption. See method "decrypt" below.

my $pt = ecc_decrypt($priv_key_filename, $ciphertext);
#or
my $pt = ecc_decrypt(\$buffer_containing_priv_key, $ciphertext);

ecc_sign_message

Elliptic Curve Digital Signature Algorithm (ECDSA) - signature generation. See method "sign_message" below.

my $sig = ecc_sign_message($priv_key_filename, $message);
#or
my $sig = ecc_sign_message(\$buffer_containing_priv_key, $message);
#or
my $sig = ecc_sign_message($priv_key, $message, $hash_name);

ecc_verify_message

Elliptic Curve Digital Signature Algorithm (ECDSA) - signature verification. See method "verify_message" below.

ecc_verify_message($pub_key_filename, $signature, $message) or die "ERROR";
#or
ecc_verify_message(\$buffer_containing_pub_key, $signature, $message) or die "ERROR";
#or
ecc_verify_message($pub_key, $signature, $message, $hash_name) or die "ERROR";

ecc_sign_hash

Elliptic Curve Digital Signature Algorithm (ECDSA) - signature generation. See method "sign_hash" below.

my $sig = ecc_sign_hash($priv_key_filename, $message_hash);
#or
my $sig = ecc_sign_hash(\$buffer_containing_priv_key, $message_hash);

ecc_verify_hash

Elliptic Curve Digital Signature Algorithm (ECDSA) - signature verification. See method "verify_hash" below.

ecc_verify_hash($pub_key_filename, $signature, $message_hash) or die "ERROR";
#or
ecc_verify_hash(\$buffer_containing_pub_key, $signature, $message_hash) or die "ERROR";

ecc_shared_secret

Elliptic curve Diffie-Hellman (ECDH) - construct a Diffie-Hellman shared secret with a private and public ECC key. See method "shared_secret" below.

#on Alice side
my $shared_secret = ecc_shared_secret('Alice_priv_ecc1.der', 'Bob_pub_ecc1.der');

#on Bob side
my $shared_secret = ecc_shared_secret('Bob_priv_ecc1.der', 'Alice_pub_ecc1.der');

METHODS

new

my $pk = Crypt::PK::ECC->new();
#or
my $pk = Crypt::PK::ECC->new($priv_or_pub_key_filename);
#or
my $pk = Crypt::PK::ECC->new(\$buffer_containing_priv_or_pub_key);

generate_key

Uses Yarrow-based cryptographically strong random number generator seeded with random data taken from /dev/random (UNIX) or CryptGenRandom (Win32).

$pk->generate_key($keysize);
# $keysize .. key size in bytes: 14, 16, 20, 24, 28, 32, 48 or 65
#   14 => use curve SECP112R1
#   16 => use curve SECP128R1
#   20 => use curve SECP160R1
#   24 => use curve P-192 recommended by FIPS 186-3
#   28 => use curve P-224 recommended by FIPS 186-3
#   32 => use curve P-256 recommended by FIPS 186-3
#   48 => use curve P-384 recommended by FIPS 186-3
#   65 => use curve P-521 recommended by FIPS 186-3

See http://csrc.nist.gov/publications/fips/fips186-3/fips_186-3.pdf and http://www.secg.org/collateral/sec2_final.pdf

import_key

$pk->import_key($filename);
#or
$pk->import_key(\$buffer_containing_key);

import_key_x963

ANSI X9.63 Import (public key only) - can load data exported by export_key_x963

$pk->import_key(\$buffer_containing_pub_key_ansi_x963);

export_key_der

my $private_der = $pk->export_key_der('private');
#or
my $public_der = $pk->export_key_der('public');

export_key_x963

ANSI X9.63 Export (public key only)

my $public_ansi_x963 = $pk->export_key_x963();

encrypt

my $pk = Crypt::PK::ECC->new($pub_key_filename);
my $ct = $pk->encrypt($message);

decrypt

my $pk = Crypt::PK::ECC->new($priv_key_filename);
my $pt = $pk->decrypt($ciphertext);

sign_message

my $pk = Crypt::PK::ECC->new($priv_key_filename);
my $signature = $priv->sign_message($message);
#or
my $signature = $priv->sign_message($message, $hash_name);

#NOTE: $hash_name can be 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by L<Crypt::Digest>

verify_message

my $pk = Crypt::PK::ECC->new($pub_key_filename);
my $valid = $pub->verify_message($signature, $message)
#or
my $valid = $pub->verify_message($signature, $message, $hash_name);

#NOTE: $hash_name can be 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by L<Crypt::Digest>

sign_hash

my $pk = Crypt::PK::ECC->new($priv_key_filename);
my $signature = $priv->sign_hash($message_hash);

verify_hash

my $pk = Crypt::PK::ECC->new($pub_key_filename);
my $valid = $pub->verify_hash($signature, $message_hash);

shared_secret

# Alice having her priv key $pk and Bob's public key $pkb
my $pk  = Crypt::PK::ECC->new($priv_key_filename);
my $pkb = Crypt::PK::ECC->new($pub_key_filename);
my $shared_secret = $pk->shared_secret($pkb);

# Bob having his priv key $pk and Alice's public key $pka
my $pk = Crypt::PK::ECC->new($priv_key_filename);
my $pka = Crypt::PK::ECC->new($pub_key_filename);
my $shared_secret = $pk->shared_secret($pka);  # same value as computed by Alice

is_private

my $rv = $pk->is_private;
# 1 .. private key loaded
# 0 .. public key loaded
# undef .. no key loaded

size

my $size = $pk->is_private;
# returns key size in bytes or undef if no key loaded

key2hash

my $hash = $pk->key2hash;

# returns hash like this (or undef if no key loaded):
{
  type => 1,
  size => 32,
  curve_name  => "ECC-256",
  curve_size  => 32,
  curve_B     => "5AC635D8AA3A93E7B3EBBD55769886BC651D06B0CC53B0F63BCE3C3E27D2604B",
  curve_Gx    => "6B17D1F2E12C4247F8BCE6E563A440F277037D812DEB33A0F4A13945D898C296",
  curve_Gy    => "4FE342E2FE1A7F9B8EE7EB4A7C0F9E162BCE33576B315ECECBB6406837BF51F5",
  curve_order => "FFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E84F3B9CAC2FC632551",
  curve_prime => "FFFFFFFF00000001000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFF",
  k => "A7F43ACD4A05D69AE4597E6E723EB5F1E9B9B7EAA51B6DE83CF36F9687B57DEE",
  pub_x => "AB53ED5D16CE550BAAF16BA4F161332AAD56D63790629C27871ED515D4FC229C",
  pub_y => "78FC34C6A320E22672A96EBB6DA48387A40541A3D7E5CFAE0D58A513E38C8888",
  pub_z => "1",
}