Name: CVE-2026-6681: Out-of-bounds Write
Creator: Rapid7
Published: 2026-06-25T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-6681, CWE-787, CWE-120, CVSS 5.3, EPSS 0.00376

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 Details

CVSS 4.0 Base Score: 1 (LOW)
CVSS 4.0 Vector: (CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Clear)
CVSS 3.1 Base Score: 5.3
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade wolfssl	Oct 19, 2026	Jun 25, 2026
Debian	—	Upgrade wolfssl	Jul 15, 2026	Jul 15, 2026

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CVSS Details

Covered by Rapid7

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