CPANSA-Crypt-DSA-2026-12205: Crypt-DSA vulnerability

Publisher giterlizzi Document category csaf_security_advisory
Initial release date 2026-06-15T00:00:00 Engine CSAF Perl Toolkit 0.26
Current release date 2026-06-15T00:00:00 Build Date
Current version 1 Status final
CVSS v3.1 Base Score 9.1 Severity
Original language Language en
Also referred to

Vulnerability Description

Crypt::DSA versions before 1.21 for Perl reused the nonce across signatures, leading to private-key recovery. Crypt::DSA::sign caches the per-signature nonce material in the Key object without ever clearing it. The first sign() on a Key object picks a nonce, and every later sign() on that same object reuses it, producing an identical "r". Keys used to sign more than once with an affected version should be considered compromised.

Vulnerabilities

CVE-2026-12205

Vulnerability Description

Crypt::DSA versions before 1.21 for Perl reused the nonce across signatures, leading to private-key recovery.

Crypt::DSA::sign caches the per-signature nonce material in the Key object without ever clearing it.

The first sign() on a Key object picks a nonce, and every later sign() on that same object reuses it, producing an identical "r".

Keys used to sign more than once with an affected version should be considered compromised.

Weakness CWE-323 : Reusing a Nonce, Key Pair in Encryption

Product status

Known affected
Product Score
Crypt-DSA less than 1.21
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:H/A:N 9.1 Critical
Fixed

giterlizzi

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

gdt@cpan.org

References

Revision history

Version Date of the revision Summary of the revision
1 Mon Jun 15 00:00:00 2026 First release

Sharing rules

TLP:WHITE
For the TLP version see: https://www.first.org/tlp/