VulnerabilityDeferred

CVE-2026-2681

This out-of-bounds stack write vulnerability, specifically in the blst_sha256_bcopy assembly routine, occurs due to a missing zero-length guard.

MEDIUM 5.3EPSS 0.30%

Does this matter?

Lower severity and a low EPSS score (0.30%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1: 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS: 0.30% probability · 23th percentile
CISA KEV: Not listed
Weakness: CWE-787
Source: patrick@puiterwijk.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.