Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS1xeHA2LTI3Z3ctOTljas4AAnWa

Time-of-check Time-of-use (TOCTOU) Race Condition in Jenkins

Due to a time-of-check to time-of-use (TOCTOU) race condition, the file browser for workspaces, archived artifacts, and $JENKINS_HOME/userContent/ follows symbolic links to locations outside the directory being browsed in Jenkins 2.275 and LTS 2.263.2.

This allows attackers with Job/Workspace permission and the ability to control workspace contents, e.g., with Job/Configure permission or the ability to change SCM contents, to create symbolic links that allow them to access files outside workspaces using the workspace browser.

This issue is caused by an incorrectly applied fix for SECURITY-1452 / CVE-2021-21602 in the 2021-01-13 security advisory.

Jenkins 2.276, LTS 2.263.3 no longer differentiates the check and the use of symlinks in workspace browsers.

Permalink: https://github.com/advisories/GHSA-qxp6-27gw-99cj
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS1xeHA2LTI3Z3ctOTljas4AAnWa
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Moderate
Classification: General
Published: about 1 year ago
Updated: 4 months ago

CVSS Score: 5.3
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Identifiers: GHSA-qxp6-27gw-99cj, CVE-2021-21615
References:

• https://nvd.nist.gov/vuln/detail/CVE-2021-21615
• https://www.jenkins.io/security/advisory/2021-01-26/#SECURITY-2197
• http://www.openwall.com/lists/oss-security/2021/01/26/2
• https://github.com/advisories/GHSA-qxp6-27gw-99cj

Affected Packages