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CVE-2026-41564

CryptX versions before 0.088 for Perl do not reseed the Crypt::PK PRNG state after forking

CVSS 7.5 HIGHEPSS 0.4%CWE-335CWE-338
In short

CryptX library for Perl doesn't reset its random number generator after a process splits (forks), causing child processes to generate identical cryptographic keys and signatures. This is dangerous in web servers that start with shared cryptographic objects, as attackers could recover private keys.

Technical detail

CryptX Crypt::PK modules initialize PRNG state in constructors without fork detection, causing child processes inheriting pre-fork objects to produce byte-identical random output. Affected operations include key generation and ECDSA/DSA signing; two signatures from different processes enable nonce-reuse attacks to recover the signing private key. Vector: preforking server architectures (e.g., Starman) where Crypt::PK objects are loaded at startup and inherited by workers.

Summary generated and translated by AI from the official description.
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
MIK · CryptX

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References
https://github.com/DCIT/perl-CryptX/commit/9a1dd3e0c27d68e32450be5538b864c2b115ee15.patchhttps://github.com/DCIT/perl-CryptX/security/advisories/GHSA-24c2-gp6c-24c6https://metacpan.org/release/MIK/CryptX-0.088http://www.openwall.com/lists/oss-security/2026/04/23/2