# CVE-2026-11310 — wolfSSL > As of 2026-06-26, CVE-2026-11310 is a High-severity (band derived from the CVSS v4.0 score, not stated by the CNA) vulnerability in wolfSSL, CVSS v4.0 8.7, EPSS 0.2% (13.1th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-11310, most recently “Multiple WolfSSL Critical Vulnerabilities: Certificate Bypass, RCE, and Post-Quantum Weakening”. **Last updated:** 2026-06-26 ## What is CVE-2026-11310? X.509 trust-chain bypass in the OpenSSL compatibility certificate verifier (wolfSSL_X509_verify_cert()). This affects only builds with --enable-opensslextra (OPENSSL_EXTRA) and whose application validates certificates by calling X509_verify_cert() with caller-supplied untrusted intermediate certificates; for those users it is critical, otherwise the library is unaffected. In particular, native wolfSSL TLS/DTLS usage is not impacted. wolfSSL's X509_verify_cert() temporarily loads each caller-supplied untrusted intermediate into the certificate manager but failed to drop them before the trusted-store check, so an untrusted intermediate could anchor the path itself. An attacker can present a chain that never reaches a configured trust anchor and have it accepted, resulting in acceptance of an attacker-controlled certificate. This is certificate verification independent of TLS (e.g. S/MIME/CMS, code/firmware signing, JWT/JWS x5c), is not specific to any key type or algorithm, and a single untrusted intermediate suffices. The default wolfSSL TLS handshake (WOLFSSL_VERIFY_PEER) is not affected; only TLS applications doing manual or deferred peer verification through this API are, which also requires --enable-sessioncerts. The record classifies CVE-2026-11310 under weakness class [CWE-295](https://intel.threadlinqs.com/cwe/CWE-295). 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 107 days ago. ## Severity and exploitation probability - **CVSS v4.0 base score:** 8.7 — High (derived from score) (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N`) - **EPSS (FIRST):** 0.2% probability of exploitation in the next 30 days, higher than 13.1% of all scored CVEs - **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog - **Threadlinqs priority:** 6.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability - **Published:** 2026-06-25, last modified 2026-06-26 ## Is CVE-2026-11310 being exploited? Weaponised exploit code for CVE-2026-11310 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 20 in the Threadlinqs vulnerability feed. - [trickest/cve](https://github.com/trickest/cve/blob/main/2026/CVE-2026-11310.md) (trickest) ## Affected products and versions - [wolfSSL](https://intel.threadlinqs.com/vendors/wolfssl): wolfSSL ## How to fix CVE-2026-11310 No vendor patch reference has been recorded for CVE-2026-11310 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise. ## Threat activity tracking CVE-2026-11310 1 tracked threat in the Threadlinqs corpus references CVE-2026-11310, either in the campaign’s CVE list or as an indicator on the campaign record. - [Multiple WolfSSL Critical Vulnerabilities: Certificate Bypass, RCE, and Post-Quantum Weakening](https://intel.threadlinqs.com/threat/TL-2026-1008) — CRITICAL · 2026-06-30 ## Sources Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-10-10. **Vendor advisory and patch** - [github.com — patch](https://github.com/wolfSSL/wolfssl/pull/10674) **Other references** - [wolfssl.com](https://www.wolfssl.com/docs/security-vulnerabilities/) Canonical: https://intel.threadlinqs.com/cve/CVE-2026-11310 Full detection coverage and IOCs for threats exploiting CVE-2026-11310 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp