Buffer overflow in Cross-crypto Cross-implementation

CVE-2026-41509

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…

Vulnerability class: Buffer Overflow

EPSS: 0.001 (19.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-41509?
CVE-2026-41509 is a critical-severity vulnerability in Cross-crypto Cross-implementation, classified under Stack-based Buffer Overflow. CVSS score: 9.8/10. Published 2026-05-08.
How severe is CVE-2026-41509?
Critical severity. CVSS v3 base score is 9.8 out of 10.