CVE-2026-0976Network attack vector

Path-filter bypass via accepted matrix parameters

Published Jan 15, 2026 · Updated Jan 15, 2026

Improper input validation in Red Hat build of Keycloak allows remote attackers to bypass reverse-proxy path filters. The JAX-RS routing layer accepts semicolon-delimited matrix parameters within path segments while the proxy can evaluate a different path. Exposure requires a reverse proxy that ignores or mishandles those parameters; Keycloak authentication still governs protected endpoint access.

CVSS severity3.7
Low
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Red Hat build of Keycloak allows remote attackers to bypass reverse-proxy path filters. The JAX-RS routing layer accepts semicolon-delimited matrix parameters within path segments while the proxy can evaluate a different path. Exposure requires a reverse proxy that ignores or mishandles those parameters; Keycloak authentication still governs protected endpoint access.

The record

CVE
CVE-2026-0976
Published
Jan 15, 2026
Updated
Jan 15, 2026
Vendor
389 Directory Server
Product
Red Hat JBoss Enterprise Application Platform Expansion Pack
Classifications
CWE-20, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

389 Directory Server · Red Hat JBoss Enterprise Application Platform Expansion PackAffected versions are unavailable in this record.
389 Directory Server · Red Hat build of KeycloakAffected versions are unavailable in this record.
389 Directory Server · Red Hat JBoss Enterprise Application PlatformAffected versions are unavailable in this record.

Published CVSS scores

3.7Red HatCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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