SB2020092202 - Multiple vulnerabilities in Jenkins Blue Ocean plugin

Description

This security bulletin contains information about 2 vulnerabilities.

1) Path traversal (CVE-ID: CVE-2020-2254)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to the affected plugin provides an undocumented feature flag, "blueocean.features.GIT_READ_SAVE_TYPE", that when set to the value "clone". A remote authenticated attacker with Item/Configure or Item/Create permission can send a specially crafted HTTP request and read arbitrary files on the system.

2) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2020-2255)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a remote attacker to escalate privileges on the system.

The vulnerability exists due to the affected plugin does not perform permission checks in several HTTP endpoints implementing connection tests. A remote user with Overall/Read permission can connect to an attacker-specified URL.

Remediation

Install update from vendor's website.

References

• http://www.openwall.com/lists/oss-security/2020/09/16/3
• https://www.jenkins.io/security/advisory/2020-09-16/#SECURITY-1956
• https://www.jenkins.io/security/advisory/2020-09-16/#SECURITY-1961