CVE-2021-21615

Jenkins 2.275 and LTS 2.263.2 allows reading arbitrary files using the file browser for workspaces and archived artifacts due to a time-of-check to time-of-use (TOCTOU) race condition.

Jenkins 2.275 and LTS 2.263.2 allows reading arbitrary files using the file browser for workspaces and archived artifacts due to a time-of-check to time-of-use (TOCTOU) race condition.

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](https://www.jenkins.io/security/advisory/2021-01-13/#SECURITY-1452). Jenkins 2.276, LTS 2.263.3 no longer differentiates the check and the use of symlinks in workspace browsers.

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](https://www.jenkins.io/security/advisory/2021-01-13/#SECURITY-1452). Jenkins 2.276, LTS 2.263.3 no longer differentiates the check and the use of symlinks in workspace browsers.

Jenkins versiones 2.275 y LTS 2.263.2, permiten leer archivos arbitrarios usando el explorador de archivos para espacios de trabajo y artefactos archivados debido a una condición de carrera de tipo time-of-check a time-of-use (TOCTOU)