CVE-2023-24456Network attack vector

Administrator access via preserved login session

Published Jan 24, 2023 · Updated Apr 2, 2025

Session fixation in Jenkins Keycloak Authentication Plugin 2.3.0 and earlier allows remote attackers to gain administrator access. During Keycloak-backed login, the plugin preserves the existing Jenkins session instead of invalidating it and establishing a new session. Exploitation requires social engineering that causes an administrator to authenticate through a Jenkins session already known to the attacker.

CVSS severity8.8
High
EPSS probability1.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Session fixation in Jenkins Keycloak Authentication Plugin 2.3.0 and earlier allows remote attackers to gain administrator access. During Keycloak-backed login, the plugin preserves the existing Jenkins session instead of invalidating it and establishing a new session. Exploitation requires social engineering that causes an administrator to authenticate through a Jenkins session already known to the attacker.

The record

CVE
CVE-2023-24456
Published
Jan 24, 2023
Updated
Apr 2, 2025
Vendor
Jenkins Project
Product
Keycloak Authentication Plugin
Classifications
CWE-384, T1539
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 24, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 2, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <=2.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Jenkins Project · Keycloak Authentication Pluginversion=unspecified <=2.3.0

Published CVSS scores

9.8NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.8Jenkins ProjectCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-384Session Fixation
T1539Steal Web Session Cookie

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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