CVE-2026-12340
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).
- Affected products
- Wolfssl, Wolfssl Jll
- Wolfssl
- < 5.9.2
- CVSS 3.1
- 7.5 HIGH
- EPSS
- 0.3% (22th percentile)
- Weakness
- CWE-125
- NVD status
- Analyzed
- Published
- 2026-06-25
CVE-2026-12340 at NVD
No indexed exploits for CVE-2026-12340 yet
Our index is partial: it proves presence, never absence
No exploit for CVE-2026-12340 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.