CVE-2026-12340 (GCVE-0-2026-12340)
Vulnerability from cvelistv5 – Published: 2026-06-25 19:36 – Updated: 2026-06-26 13:59
VLAI
EPSS
VEX
Title
Out-of-bounds heap read in SM2/SM3 certificate Subject Key Identifier computation
Summary
Out-of-bounds heap read during SM2/SM3 certificate signature verification. When parsing a certificate with an SM3wSM2 signature, the Subject Key Identifier computation reads the trailing 65 bytes of the public key without checking that the key is at least that long. A public key shorter than 65 bytes results in an out-of-bounds heap read, leading to a potential crash (denial of service); there is no out-of-bounds write. Note this only affects builds with SM2 support (--enable-sm2 or --enable-all).
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-26 13:59 UTC
CWE
- CWE-125 - Out-of-bounds Read
Assigner
References
2 references
Impacted products
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