CVE-2026-41509

Integer underflow in crypto_sign_open() leads to buffer overflow

Published May 8, 2026 CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed
Description
CROSS implementation contains reference and optimized implementations of the CROSS post-quantum signature algorithm. Prior to commit fc6b7e7, there is a buffer overflow in crypto_sign_open() caused by an underflow of the integer mlen. This issue has been patched via commit fc6b7e7.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Cross-crypto
Cross-crypto cross-implementation
CPEs cpe:2.3:a:cross-crypto:cross-implementation:*:*:*:*:*:*:*:*
Vendors & Products Cross-crypto
Cross-crypto cross-implementation
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Type Values Removed Values Added
First Time appeared Cross-signature
Cross-signature cross-implementation
Vendors & Products Cross-signature
Cross-signature cross-implementation
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description CROSS implementation contains reference and optimized implementations of the CROSS post-quantum signature algorithm. Prior to commit fc6b7e7, there is a buffer overflow in crypto_sign_open() caused by an underflow of the integer mlen. This issue has been patched via commit fc6b7e7.
Title Integer underflow in crypto_sign_open() leads to buffer overflow
Weaknesses CWE-121
CWE-122
References
Metrics cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 8, 2026, 2:15 PM
Reserved
Apr 20, 2026, 6:18 PM
Status
Analyzed
Published
May 8, 2026, 2:16 PM
Modified
Oct 26, 2026, 7:10 PM