CVE-2018-1000861Known exploitationPublic exploitNetwork attack vectorHinoki check available

Code execution via unrestricted reflective URL routing

Published Dec 10, 2018 · Updated Oct 21, 2025

Code execution in Stapler in Jenkins weekly 2.153 and earlier allows attackers to invoke Java methods via crafted URLs. Stapler's MetaClass.java routes URL segments to reachable Java objects through reflection, exposing methods that match naming conventions without requiring intended HTTP accessibility. Jenkins LTS 2.138.3 and earlier is also affected; permissions and installed plugins determine reachable effects, including unauthenticated session invalidation on Winstone-Jetty.

CVSS severity9.8
Critical
EPSS probability98.33%
Next 30 days · Nov 1, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Code execution in Stapler in Jenkins weekly 2.153 and earlier allows attackers to invoke Java methods via crafted URLs. Stapler's MetaClass.java routes URL segments to reachable Java objects through reflection, exposing methods that match naming conventions without requiring intended HTTP accessibility. Jenkins LTS 2.138.3 and earlier is also affected; permissions and installed plugins determine reachable effects, including unauthenticated session invalidation on Winstone-Jetty.

The record

CVE
CVE-2018-1000861
Published
Dec 10, 2018
Updated
Oct 21, 2025
Vendor
Jenkins Project
Product
Jenkins
Classifications
CWE-502, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 10, 2018CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 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=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Jenkins Project · Jenkinsversion=n/a

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8GitHub Advisory DatabaseCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E: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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsShadowserver observations through Sep 28, 2026. Gaps indicate unavailable data.
Sep 22, 2026Sep 28, 2026
View daily counts
Reporting dayUnique IPs
Sep 22, 20261
Sep 23, 20261
Sep 24, 2026Unavailable
Sep 25, 2026Unavailable
Sep 26, 2026Unavailable
Sep 27, 2026Unavailable
Sep 28, 2026Unavailable
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

Public exploit references

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

Reported exploitation

Technologies

Your stack

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Your stack

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