Vulnerability · Published Jun 25, 2026 · Assigned by wolfSSL

CVE-2026-11999X.509 trust-chain bypass via path-depth exhaustion in wolfSSL_X509_verify_cert()

High 8.2

In plain English

A high-severity improper certificate validation 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 0.2% (higher than 14% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)8.2High
Exploit odds (30 days)0.2%top 85.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

X.509 trust-chain bypass (path-depth exhaustion) in the OpenSSL compatibility certificate verifier (wolfSSL_X509_verify_cert()). This affects only builds with --enable-opensslextra whose application calls X509_verify_cert() with caller-supplied untrusted intermediates; for those users it is critical, otherwise the library is unaffected. Native wolfSSL TLS/DTLS usage is not impacted. X509_verify_cert() returned success based only on the last verified link rather than on reaching a trust anchor: when the supplied chain is deeper than the verifier's maximum path depth (default 100), path building runs out of depth while still walking untrusted intermediates and the chain is accepted even though it never reaches a configured trust anchor, allowing acceptance of an attacker-controlled certificate. The default TLS handshake (WOLFSSL_VERIFY_PEER) is not affected; only applications doing manual or deferred verification through this API are.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.24wolfssl5.9.2-r0ALPINE-CVE-2026-11999
Debian:12wolfsslno fix listedDEBIAN-CVE-2026-11999
Debian:13wolfsslno fix listedDEBIAN-CVE-2026-11999
Ubuntu:22.04:LTSwolfsslno fix listedUBUNTU-CVE-2026-11999
Ubuntu:24.04:LTSwolfsslno fix listedUBUNTU-CVE-2026-11999
Ubuntu:25.10wolfsslno fix listedUBUNTU-CVE-2026-11999
Ubuntu:26.04:LTSwolfsslno fix listedUBUNTU-CVE-2026-11999
Ubuntu:26.10wolfsslno fix listedUBUNTU-CVE-2026-11999

Affected products (as reported)

VendorProductVersions
wolfSSL wolfSSL 5.7.4 – through 5.9.1

Weakness: CWE-295 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

References