CVE-2026-12205

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.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://metacpan.org/release/TIMLEGGE/Crypt-DSA-1.20/source/lib/Crypt/DSA.pm#L47
https://metacpan.org/release/TIMLEGGE/Crypt-DSA-1.21/changes
http://www.openwall.com/lists/oss-security/2026/06/15/4

Configurations

No configuration.

History

25 Oct 2026, 23:10

Type	Values Removed	Values Added
Summary		(es) Las versiones de Crypt::DSA anteriores a la 1.21 para Perl reutilizaban el nonce entre firmas, lo que llevaba a la recuperación de la clave privada. Crypt::DSA::sign cachea el material nonce por firma en el objeto Key sin borrarlo nunca. El primer sign() en un objeto Key elige un nonce, y cada sign() posterior en ese mismo objeto lo reutiliza, produciendo una ’r’ idéntica. Las claves utilizadas para firmar más de una vez con una versión afectada deben considerarse comprometidas.

Information

Published : 2026-06-15 23:16

Updated : 2026-10-25 23:10

NVD link : CVE-2026-12205

Mitre link : CVE-2026-12205

CVE.ORG link : CVE-2026-12205

JSON object : View

Products Affected

No product.

CWE

CWE-323

Reusing a Nonce, Key Pair in Encryption

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