6.5

CVE-2026-89135: Failed X509_verify_cert leaves unverified CA in shared CertManager

Analyzed
AliasesUBUNTU-CVE-2026-89135DEBIAN-CVE-2026-89135ALPINE-CVE-2026-89135
Published 27-09-2026Last modified 29-09-2026

Vulnerability summary

CVE-2026-89135 is a medium (CVSS 6.5) Improper Certificate Validation vulnerability in wolfssl. EPSS estimates a 0.11% chance of exploitation in the next 30 days, higher than 1.3% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 6.3, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.11%
0%100%
Low · -0.04 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 27-09-2026
    PublishedVulnerability first disclosed.
  2. 29-09-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

7 scores · 5 sources · 2 versions

EPSS trend

Probability

0.11%

Chance of exploitation in the next 30 days

Percentile

1%

Versus all other CVEs

30-day change

Decrease -0.04 pp

From 0.15% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine1 product
  • wolfssl≥ 5.8.4, < 5.9.4-r0
Debian1 product
  • wolfsslAll versions (No fix recorded)
Ubuntu1 product
  • wolfsslAll versions (No fix recorded)
Wolfssl1 product

4 vendors · 4 products

References

5 links