CVE-2026-2681 PUBLISHED

Github.com/supranational/blst: blst cryptographic library: denial of service via out-of-bounds stack write in key generation

Assigner: fedora
Reserved: 18.02.2026 Published: 19.02.2026 Updated: 19.02.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS Score: 5.3

Product Status

Package Collection https://github.com/supranational/blst
Package Name blst
Versions Default: unaffected
  • affected from 0 to 0.3.16 (incl.)

Workarounds

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Credits

  • Red Hat would like to thank Kr0emer for reporting this issue.

References

Problem Types

  • Out-of-bounds Write CWE