CVE-2026-77696

CVE CVE-2026-77696EUVD EUVD-2026-89012Published 2026-09-29T15:32:22.000ZLast changed 2026-09-29T16:51:33.000ZCVSS 3.7

What the advisory describes

Issue summary: SM2 signature generation uses non-constant-time arithmetic on secret values, forming a timing side-channel. Impact summary: An attacker able to measure SM2 signing times may learn information about the per-signature secret nonce, which over many signatures can, via a lattice / Hidden Number Problem attack, lead to recovery of the private key. CWE: CWE-208: Observable Timing Discrepancy Description: SM2 signature generation computes the signature value using variable-time BIGNUM operations on the secret nonce and the private key, so the time taken to produce an SM2 signature depends on these secret values, forming a timing side-channel. Applications performing SM2 signature generation are affected on all platforms. FIPS Impact: no SM2 is not a FIPS algorithm.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

• OpenSSL — OpenSSL 3.0.0 <3.0.23; 3.6.0 <3.6.5; 4.0.0 <4.0.3; 3.4.0 <3.4.8; 3.5.0 <3.5.9; 1.1.1 <1.1.1zj

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

• OpenSSL — OpenSSL

Patchlage reports hits and suspected hits. About everything else this system says nothing — neither this page nor the situation report ever claims that an estate is safe.