CVE-2026-2681 (GCVE-0-2026-2681)
Vulnerability from cvelistv5 – Published: 2026-02-19 06:58 – Updated: 2026-02-19 21:32
VLAI
EPSS
VEX
Title
Github.com/supranational/blst: blst cryptographic library: denial of service via out-of-bounds stack write in key generation
Summary
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.
Severity
5.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-19 21:32 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
fedora
CNA
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-2681 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2440580 | issue-trackingx_refsource_REDHAT |
Date Public
2026-02-18 00:00
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