CVE-2026-77696 (GCVE-0-2026-77696)
Vulnerability from cvelistv5
Published
2026-09-29 15:32
Modified
2026-09-29 16:51
Severity ?
CWE
  • CWE-208 - Observable Timing Discrepancy
Summary
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.
References
Impacted products
Vendor Product Version
OpenSSL OpenSSL Version: 4.0.0   ≤
Version: 3.6.0   ≤
Version: 3.5.0   ≤
Version: 3.4.0   ≤
Version: 3.0.0   ≤
Version: 1.1.1   < 1.1.1zj
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