CVE-2026-6681

The PKCS#7 decode path ignores the caller-supplied output buffer size (outputSz), allowing decoded content to be written past the bounds of the provided buffer. This affects wolfSSL 5.9.0 and earlier and was fixed in the 5.9.1 release.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10116	Issue Tracking Patch
https://www.wolfssl.com/docs/security-vulnerabilities/	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

27 Jun 2026, 20:02

Type	Values Removed	Values Added
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3
First Time		Wolfssl wolfssl Wolfssl
References	~~() https://github.com/wolfSSL/wolfssl/pull/10116 -~~	() https://github.com/wolfSSL/wolfssl/pull/10116 - Issue Tracking, Patch
References	~~() https://www.wolfssl.com/docs/security-vulnerabilities/ -~~	() https://www.wolfssl.com/docs/security-vulnerabilities/ - Vendor Advisory

25 Jun 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 21:16

Updated : 2026-06-27 20:02

NVD link : CVE-2026-6681

Mitre link : CVE-2026-6681

CVE.ORG link : CVE-2026-6681

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CWE-787

Out-of-bounds Write

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