Buffer overflow in Wolfssl

CVE-2026-3548

Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.

Vulnerability class: Buffer Overflow

EPSS: 0.005 (38.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-3548?
CVE-2026-3548 is a critical-severity vulnerability in Wolfssl, classified under Heap-based Buffer Overflow. CVSS score: 9.8/10. Published 2026-03-19.
How severe is CVE-2026-3548?
Critical severity. CVSS v3 base score is 9.8 out of 10.