How severe is CVE-2026-27100?

CVE-2026-27100 has a CVSS score of 4.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2026-27100?

CVE-2026-27100 affects the following packages: org.jenkins-ci.main:jenkins-core (Maven), org.jenkins-ci.main:jenkins-core (Maven). Ecosystems affected: Maven.

How do I fix CVE-2026-27100?

Update org.jenkins-ci.main:jenkins-core to 2.551 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-27100 is resolved across your whole dependency graph.

How do I detect CVE-2026-27100 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.jenkins-ci.main:jenkins-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-27100 if there is no patch (or I can't update yet)?

Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Is CVE-2026-27100 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-27100 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-27100?

CVE-2026-27100 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 31th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-27100?

CVE-2026-27100 is classified as Information Exposure (CWE-200). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-27100 published, and has it been updated?

CVE-2026-27100 was published on February 18, 2026 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

MEDIUM severity

CVE-2026-27100 — jenkins-core

MEDIUMFix: jenkinsci/jenkins@f92eadb

CVE-2026-27100 is a medium-severity (CVSS 4.3) Information Exposure vulnerability in org.jenkins-ci.main:jenkins-core. A fix is available for org.jenkins-ci.main:jenkins-core — see the affected versions and patch details below.

Jenkins has a build information disclosure vulnerability through Run Parameter

Also known asBIT-jenkins-2026-27100GHSA-wfhp-qgm8-5p5c

Published

Feb 18, 2026

Updated

Oct 24, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-27100.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs31th percentile — riskier than 31% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

2 pkgs affected

☕org.jenkins-ci.main:jenkins-core☕org.jenkins-ci.main:jenkins-core

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Jenkins 2.550 and earlier, LTS 2.541.1 and earlier accepts Run Parameter values that refer to builds the user submitting the build does not have access to, allowing attackers with Item/Build and Item/Configure permission to obtain information about the existence of jobs, the existence of builds, and if a specified build exists, its display name.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.jenkins-ci.main:jenkins-core`	≥ 2.542&&< 2.551	2.551`org.jenkins-ci.main:jenkins-core:2.551`
☕Maven	`org.jenkins-ci.main:jenkins-core`	all versions	2.541.2`org.jenkins-ci.main:jenkins-core:2.541.2`

Affected Products

1 product · 2 configurations

Application

jenkinsjenkins

< 2.551

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.jenkins-ci.main:jenkins-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.jenkins-ci.main:jenkins-core to 2.551 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-27100 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

This information disclosure vulnerability in Jenkins allows an attacker with Item/Build and Item/Configure permissions to gain knowledge about the existence and display names of jobs and builds they are not authorized to access. This affects Jenkins instances in OpenShift Developer Tools & Services.

Product	Fixed in	Advisory
OpenShift Developer Tools and Services 4.12	`ocp-tools-4/jenkins-rhel8:1776764096`	RHSA-2026:10209
OpenShift Developer Tools and Services 4.13	`ocp-tools-4/jenkins-rhel8:1776764096`	RHSA-2026:10201
OpenShift Developer Tools and Services 4.14	`ocp-tools-4/jenkins-rhel8:1776762347`	RHSA-2026:10211
OpenShift Developer Tools and Services 4.15	`ocp-tools-4/jenkins-rhel8:1776762347`	RHSA-2026:10204
OpenShift Developer Tools and Services 4.16	`ocp-tools-4/jenkins-rhel9:1776944215`	RHSA-2026:10214
OpenShift Developer Tools and Services 4.17	`ocp-tools-4/jenkins-rhel9:1776944215`	RHSA-2026:10213
OpenShift Developer Tools and Services 4.18	`ocp-tools-4/jenkins-rhel9:1776944215`	RHSA-2026:10215
OpenShift Developer Tools and Services 4.19	`ocp-tools-4/jenkins-rhel9:1776944215`	RHSA-2026:10206

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2026-27100 in your dependencies?

Find it across Maven, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

4.3/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Raw vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

CWE Classification

CWE-200Information Exposure

Weaponization

No Nuclei template, Metasploit module or public proof-of-concept found.

OpenSSF Scorecard

Package health score

jenkins

6.4/10

Code-Review6/10

Maintained10/10

Branch-Protection3/10

Assessed Oct 26, 2026

Timeline

Disclosed

Feb 18, 2026

Last updated

Oct 24, 2026

Identifiers

CVE-2026-27100

GHSA-wfhp-qgm8-5p5c

BIT-jenkins-2026-27100

References

Advisoryjenkins.io · 2026 02 18 Advisorynvd.nist.gov · CVE 2026 27100 Webgithub.com · f92eadb5813f04ca27439455e2573c3171e93a45 Webgithub.com · jenkins 2.541.2 Webgithub.com · jenkins 2.551 Packagegithub.com · jenkins

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs affecting jenkins-core are rated as high or higher (top: high).

CVE-2026-53436CVE-2026-53437CVE-2026-53440CVE-2026-53441CVE-2026-53439CVE-2026-53435CVE-2026-53442CVE-2026-53438

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 24, 2026

CVE-2026-27100 — jenkins-core

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2026-27100 in your dependencies?