CVE Intelligence
Medium Cryptography

CVE-2026-95503 — Keycloak-services: keycloak-services: potential kdc spoofing bypass when kerberos password authentication is enabled

A flaw was found in the Kerberos federation provider of Keycloak, an open-source identity and access management solution. When Kerberos password authentication is used without SPNEGO, the system fails to verify the identity of the Key Distribution Center (KDC) by requesting a server ticket. This allows an attacker on the same network to spoof the KDC and bypass the authentication process, potentially gaining unauthorized access to user accounts.

Published Sep 22, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: redhat

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
—
No EPSS score.
Affects
Red Hat
Build Of Keycloak and 1 more
CVSS base
6.8
Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Red Hat Build Of Keycloak, Red Hat Red Hat Single Sign-On 7).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (cryptography), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Red Hat Build Of Keycloak versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Single Sign-On 7 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Adjacent
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
6.8 CVSS 3.1 Medium 1.6 5.2 secalert@redhat.com via NIST National Vulnerability Database
6.8 CVSS 3.1 Medium — — redhat via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N (score shown at the top: secalert@redhat.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-347 · Improper Verification of Cryptographic Signature

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Check TLS negotiations and unexpected certificates in the component’s traffic.
network IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · red hat/red hat build of keycloak, red hat/red hat single sign-on 7
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 15, 2026
  • CVSS changed · 6.8
    Oct 15, 2026 · NIST National Vulnerability Database
  • Source status changed · → Awaiting Analysis
    Oct 15, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVE published
    Sep 22, 2026 · redhat

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

2 on the record

Elsewhere on this site

Red Hat
every CVE for this vendor
Cryptography
same class
CWE-347
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-84823 Org.wildfly.core: wildfly: path traversal in take-snapshot discloses the server configuration to the monitor role 3h
  • CVE-2026-85634 Wildfly-core: wildfly-core: deployer rbac role privilege escalation via path traversal in deployment name 10h
  • CVE-2026-109082 Keycloak-services: keycloak-services: ciba confidential-only contract not enforced for public clients 3d
  • CVE-2026-107889 Keycloak-services: keycloak-services: stored xss on login page via kcsanitize bypass 6d
  • CVE-2026-107623 Keycloak-services: keycloak-services: oidc dcr read-modify-write silently disables offline token revocation 7d
  • CVE-2026-107604 Keycloak-services: keycloak-services: view-clients role allows retrieval of active client secrets via installation provider endpoints 7d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No FIRST EPSS score.
  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-95503 is "Keycloak-services: keycloak-services: potential kdc spoofing bypass when kerberos password authentication is enabled", rated Medium. It affects Build Of Keycloak (Red Hat); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.8 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.

Sign in or create an account to comment and suggest corrections.