Vulnerability · Published Apr 9, 2026 · Assigned by wolfSSL
CVE-2026-5447Heap buffer overflow in CertFromX509() via AuthorityKeyIdentifier
Medium 6.3
In plain English
A medium-severity heap buffer overflow in wolfSSL from wolfSSL. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 4.0)6.3Medium
Exploit odds (30 days)0.4%top 70.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | wolfssl | 5.9.1-r0 | ALPINE-CVE-2026-5447 |
| Alpine:v3.24 | wolfssl | 5.9.1-r0 | ALPINE-CVE-2026-5447 |
| Debian:12 | wolfssl | no fix listed | DEBIAN-CVE-2026-5447 |
| Debian:13 | wolfssl | no fix listed | DEBIAN-CVE-2026-5447 |
| Ubuntu:22.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-5447 |
| Ubuntu:24.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-5447 |
| Ubuntu:25.10 | wolfssl | no fix listed | UBUNTU-CVE-2026-5447 |
| Ubuntu:26.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-5447 |
| Ubuntu:26.10 | wolfssl | no fix listed | UBUNTU-CVE-2026-5447 |
Affected products (as reported)
Weakness: CWE-122 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N