CVE-2021-21656Network attack vector

Secret extraction and SSRF via external entities

Published May 11, 2021 · Updated Aug 3, 2024

XXE in Jenkins Xcode integration Plugin 2.0.14 and earlier allows remote authenticated users to extract secrets via crafted workspace files. XcodeProjectParser creates XML document builders without disabling DTDs or external entities before parsing scheme and workspace XML. Exploitation requires control of Xcode build-step input and permits reading controller secrets or making server-side requests.

CVSS severity7.1
High
EPSS probability1.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

XXE in Jenkins Xcode integration Plugin 2.0.14 and earlier allows remote authenticated users to extract secrets via crafted workspace files. XcodeProjectParser creates XML document builders without disabling DTDs or external entities before parsing scheme and workspace XML. Exploitation requires control of Xcode build-step input and permits reading controller secrets or making server-side requests.

The record

CVE
CVE-2021-21656
Published
May 11, 2021
Updated
Aug 3, 2024
Vendor
Jenkins Project
Product
Xcode integration
Classifications
CWE-611, T1005
Attack vector
network
Privileges
authenticated

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 <=2.0.14

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Jenkins Project · Xcode integrationversion=unspecified <=2.0.14

Published CVSS scores

7.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
5.5NIST NVDAV:N/AC:L/Au:S/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-611Improper Restriction of XML External Entity Reference
T1005Data from Local System

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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