CVE-2026-12340 (GCVE-0-2026-12340)

Vulnerability from cvelistv5 – Published: 2026-06-25 19:36 – Updated: 2026-06-25 19:36
VLAI
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
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CWE
Assigner
References
Impacted products
Vendor Product Version
wolfSSL wolfSSL Affected: 5.6.4 , ≤ 5.9.1 (semver)
Create a notification for this product.
Credits
David Pokora, Trail of Bits (in collaboration with Anthropic)
Show details on NVD website
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            "valueDensity": "NOT_DEFINED",
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          "url": "https://github.com/wolfSSL/wolfssl/pull/10641"
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