CPANSA-CryptX-2026-41564: CryptX vulnerability

Publisher giterlizzi Document category csaf_security_advisory
Initial release date 2026-04-23T00:00:00 Engine CSAF Perl Toolkit 0.26
Current release date 2026-04-23T00:00:00 Build Date
Current version 1 Status final
CVSS v3.1 Base Score 7.5 Severity
Original language Language en
Also referred to

Vulnerability 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.

Vulnerabilities

CVE-2026-41564

Vulnerability 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.

Weakness CWE-335 : Incorrect Usage of Seeds in Pseudo-Random Number Generator (PRNG)

Product status

Known affected
Product Score
CryptX less than 0.088
CVSS Version CVSS Vector CVSS Base Score CVSS Base Severity
3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 7.5 High
Fixed

giterlizzi

Namespace: https://github.com/giterlizzi/

gdt@cpan.org

References

Revision history

Version Date of the revision Summary of the revision
1 Thu Apr 23 00:00:00 2026 First release

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