CVE-2026-89133

mediumpriority · track · 21EPSS 0.001 · 2 %ileUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.13% (2nd) EPSS
CVSS 5.3 · medium
Is it mine?
1 products
Check your exposure
Who says so?
1 sources
nvd

EPSS · scored 2026-10-27

wolfSSL versions 5.9.2 and earlier contain a flaw in the X.509 certificate validation logic where it fails to properly enforce NameConstraints extensions when there is an unconstrained CA tier between a name-constrained intermediate CA and the leaf certificate. wolfSSL incorrectly accepted certificates for hostnames they shouldn't be allowed to cover, due to a chain-walking state-machine bug that resets the validation state when encountering an intermediate without NameConstraints, thereby bypassing cryptographic delegation controls. This defect exists in the default build configuration that makes use of certificates where name constraint extensions are used. Thanks to Jack Lloyd, PathDiff, and Ben Smyth for reporting the issue.

01

cvss

Technical severity, 0–10. One row per scoring source.

6.3
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.7–6.3

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4
v4.06.3mediumCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · facts@wolfssl.com
v4.01.7lowCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

affected products (1)

Products and version ranges known to be affected.

05

sources

Which sources assert this record, and when.

published 2026-09-27modified 2026-10-02
06

references (1) nvd

External citations — patches, advisories, analysis.

scry

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