Description
A flaw was found in the blst cryptographic library. This out-of-bounds stack write vulnerability, specifically in the blst_sha256_bcopy assembly routine, occurs due to a missing zero-length guard. A remote attacker can exploit this by providing a zero-length salt parameter to key generation functions, such as blst_keygen_v5(), if the application exposes this functionality. Successful exploitation leads to memory corruption and immediate process termination, resulting in a denial-of-service (DoS) condition.
Problem types
Product status
Any version
Timeline
| 2026-02-18: | Reported to Red Hat. |
| 2026-02-18: | Made public. |
Credits
Red Hat would like to thank Kr0emer for reporting this issue.
References
access.redhat.com/security/cve/CVE-2026-2681
bugzilla.redhat.com/show_bug.cgi?id=2440580 (RHBZ#2440580)