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

MITRE NVD CVE.ORG JSON API Print: PDF PDF

Summary

CVECVE-2026-12205
StatePUBLISHED
AssignerCPANSec
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-06-15 23:16:43 UTC
Updated2026-06-16 17:16:32 UTC
DescriptionCrypt::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.

Risk And Classification

Primary CVSS: v3.1 9.1 CRITICAL from ADP

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Problem Types: CWE-323 | CWE-323 CWE-323 Reusing a Nonce, Key Pair in Encryption

VersionSourceTypeScoreSeverityVector
3.1ADPDECLARED9.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
3.1134c704f-9b21-4f2e-91b3-4a467353bcc0Secondary9.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA TIMLEGGE CryptDSA affected 1.21 custom Not specified

References

ReferenceSourceLinkTags
www.openwall.com/lists/oss-security/2026/06/15/4 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com
metacpan.org/release/TIMLEGGE/Crypt-DSA-1.21/changes 9b29abf9-4ab0-4765-b253-1875cd9b441e metacpan.org
metacpan.org/release/TIMLEGGE/Crypt-DSA-1.20/source/lib/Crypt/DSA.pm 9b29abf9-4ab0-4765-b253-1875cd9b441e metacpan.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Richard Kettlewell (en)

Additional Advisory Data

SourceTimeEvent
CNA2026-05-16T00:00:00.000ZMaintainer contacted
CNA2026-06-13T00:00:00.000ZMaintainer and CPANSec contacted
CNA2026-06-14T00:00:00.000ZFixed version released

Solutions

CNA: Upgrade to version 1.21 Revoke any keys that may have been compromised. Crypt::DSA was deprecated in version 1.20. You should migrate to another solution.

© CVE.report 2026 |

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report