CVE intelligence

CVE-2026-89135

Vulnerability intelligence

Published Sep 27, 2026Sources checked Oct 3, 2026

6.5MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-89135 and is rated Medium severity with a CVSS score of 6.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Release Notes

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-89135?

A failed X509_verify_cert call permanently plants an unverified attacker CA in the shared CertManager, bypassing certificate validation in every type-blind sibling consumer (native TLS, OCSP, CRL, direct CM verify). This affects version 5.8.4 through 5.9.2 of wolfSSL with the macros (OPENSSL_EXTRA && !NO_CERTS && !WOLFCRYPT_ONLY) defined or built with --enable-opensslextra and the application is specifically making calls to the X509_verify_cert function.