CVE-2026-6681
LOW 1The 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.
NO EXPLOITATION SIGNALS
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
0.3%chance of exploitation in 30 days · 17th percentile
○ In CISA KEV
○ Public exploit / PoC
Impact if exploited
1CVSS 4.0 · LOW
- ConfidentialityNone
- IntegrityLow
- AvailabilityNone
What an attacker needs
- ⚠Access: Must sit on the same / adjacent network
- ⚠Privileges: Requires a low-privilege account
- ⚠User interaction: Succeeds with passive user activity
- ✓Complexity: No special conditions — reliably repeatable
- ⚠Requirements: Specific conditions must be present
✓ lowers the bar for an attacker · ⚠ raises it
Weakness (CWE)
- CWE-787: Out-of-bounds write
- CWE-120: Classic buffer overflow
CVSS 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/U:Clear