CVE-2026-6681

PKCS#7 decode ignores caller output buffer size, writing past buffer bounds

MEDIUM
5.3
CVSS Score
Published: June 25, 2026 at 08:11 PM UTC
Updated: June 27, 2026 at 08:27 PM UTC
1 product affected across 1 vendorwolfSSL

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.10.0 ≤ v ≤ 5.9.03.10.0
Affected range stops below 5.9.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

PatchIssue Tracking
Source: cverecord
https://github.com/wolfSSL/wolfssl/pull/10116

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-787CWE-120

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