CVE-2021-21663Network attack vector

Credential theft via unchecked form validation

Published Jun 10, 2021 · Updated Aug 3, 2024

Missing authorization in Jenkins XebiaLabs XL Deploy Plugin 10.0.1 and earlier lets remote authenticated users capture stored credentials. A form-validation method accepts an attacker-controlled URL and credential ID without checking the caller's permission, then authenticates outbound with the selected username and password. Overall/Read access and a credential ID obtained through another method are required; successful use discloses that stored credential.

CVSS severity4.3
Medium
EPSS probability1.00%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Jenkins XebiaLabs XL Deploy Plugin 10.0.1 and earlier lets remote authenticated users capture stored credentials. A form-validation method accepts an attacker-controlled URL and credential ID without checking the caller's permission, then authenticates outbound with the selected username and password. Overall/Read access and a credential ID obtained through another method are required; successful use discloses that stored credential.

The record

CVE
CVE-2021-21663
Published
Jun 10, 2021
Updated
Aug 3, 2024
Vendor
Jenkins Project
Product
XebiaLabs XL Deploy Plugin
Classifications
CWE-862, T1555
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 10, 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=7.5.6 <unspecified
  2. Affected versionversion=unspecified <=7.5.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Jenkins Project · XebiaLabs XL Deploy Pluginversion=7.5.6 <unspecified; version=unspecified <=7.5.8

Published CVSS scores

4.3GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
T1555Credentials from Password Stores

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

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Your stack

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