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).
Published: 2026-06-25
Score: 6.3 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

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Tracking

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History

Fri, 26 Jun 2026 14:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 26 Jun 2026 01:15:00 +0000

Type Values Removed Values Added
First Time appeared Wolfssl
Wolfssl wolfssl
Vendors & Products Wolfssl
Wolfssl wolfssl

Thu, 25 Jun 2026 20:00:00 +0000

Type Values Removed Values Added
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).
Title Out-of-bounds heap read in SM2/SM3 certificate Subject Key Identifier computation
Weaknesses CWE-125
References
Metrics cvssV4_0

{'score': 6.3, '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'}


cve-icon MITRE

Status: PUBLISHED

Assigner: wolfSSL

Published:

Updated: 2026-06-26T13:59:21.953Z

Reserved: 2026-06-15T16:30:26.001Z

Link: CVE-2026-12340

cve-icon Vulnrichment

Updated: 2026-06-26T13:59:18.441Z

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-06-26T01:00:05Z

Weaknesses