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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-12340 Detail

Description

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).


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  wolfSSL Inc.
CVSS-B 6.3 MEDIUM
Vector:  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

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/wolfSSL/wolfssl/pull/10641 wolfSSL Inc. Issue Tracking  Patch 
https://www.wolfssl.com/docs/security-vulnerabilities/ wolfSSL Inc. Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-125 Out-of-bounds Read wolfSSL Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-12340
NVD Published Date:
06/25/2026
NVD Last Modified:
06/26/2026
Source:
wolfSSL Inc.