CVE-2026-5447 Heap buffer overflow in CertFromX509() via AuthorityKeyIdentifier
A heap buffer overflow in wolfSSL allows attackers to execute arbitrary code or cause denial of service via malicious X.509 certificates.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-5447?
CVE-2026-5447 is a medium-severity memory corruption vulnerability in Wolfssl Wolfssl, published on 9 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Heap buffer overflow in CertFromX509 via AuthorityKeyIdentifier size confusion. A heap buffer overflow occurs when converting an X.509 certificate internally due to incorrect size handling of the AuthorityKeyIdentifier extension.
Weakness: CWE-122
Which versions are affected by CVE-2026-5447?
It affects 1 product.
Products include Wolfssl Wolfssl.
How do I fix CVE-2026-5447?
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-2026-5447 being exploited?
There is no known exploitation of CVE-2026-5447 in the wild and no public exploit code.
Other vulnerabilities in Wolfssl Wolfssl
Sources
Also known as DEBIAN-CVE-2026-5447, GHSA-mx4j-fjqx-f8qj, JLSEC-2026-723, UBUNTU-CVE-2026-5447.