CVE-2026-3548 Buffer overflow in CRL number parsing in wolfSSL
Attackers can trigger heap or stack buffer overflows in wolfSSL by providing crafted CRLs, potentially leading to code execution or crashes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-3548?
CVE-2026-3548 is a high-severity memory corruption vulnerability in Wolfssl Wolfssl, published on 19 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-3548?
It affects 1 product.
Products include Wolfssl Wolfssl.
How do I fix CVE-2026-3548?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-3548 being exploited?
There is no known exploitation of CVE-2026-3548 in the wild and no public exploit code.
Other vulnerabilities in Wolfssl Wolfssl
Sources
Also known as DEBIAN-CVE-2026-3548, GHSA-86fv-q5vx-mw5m, JLSEC-2026-707, UBUNTU-CVE-2026-3548.