CVE-2021-21655Network attack vector

Unauthorized outbound connections via CSRF-prone test endpoints

Published May 11, 2021 · Updated Aug 3, 2024

CSRF in Jenkins P4 Plugin 1.11.4 and earlier allows remote attackers to make Jenkins connect to an attacker-controlled Perforce server. Multiple connection-test HTTP endpoints accept non-POST requests and use attacker-supplied server, username, and password values. Exploitation requires a Jenkins user to load a crafted request and directs a server-side connection without exposing stored Jenkins credentials.

CVSS severity7.1
High
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

CSRF in Jenkins P4 Plugin 1.11.4 and earlier allows remote attackers to make Jenkins connect to an attacker-controlled Perforce server. Multiple connection-test HTTP endpoints accept non-POST requests and use attacker-supplied server, username, and password values. Exploitation requires a Jenkins user to load a crafted request and directs a server-side connection without exposing stored Jenkins credentials.

The record

CVE
CVE-2021-21655
Published
May 11, 2021
Updated
Aug 3, 2024
Vendor
Jenkins Project
Product
P4 Plugin
Classifications
CWE-352
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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 <=1.11.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Jenkins Project · P4 Pluginversion=unspecified <=1.11.4

Published CVSS scores

7.1NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
5.8NISTAV:N/AC:M/Au:N/C:P/I:P/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 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-352Cross-Site Request Forgery (CSRF)

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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