SB2021070108 - Multiple vulnerabilities in Jenkins and Jenkins LTS

Description

This security bulletin contains information about 2 vulnerabilities.

1) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2021-21670)

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 application does not properly impose security restrictions. A remote authenticated attacker can cancel queue items and abort builds of jobs for which they have Item/Cancel permission even when they do not have Item/Read permission. 

2) Session Fixation (CVE-ID: CVE-2021-21671)

CWE-ID: CWE-384 - Session Fixation

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

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the affected product does not invalidate the existing session on login. A remote attacker can use social engineering techniques to gain administrator access to Jenkins.

Remediation

Install update from vendor's website.

References

• https://www.jenkins.io/security/advisory/2021-06-30/#SECURITY-2278
• https://www.jenkins.io/security/advisory/2021-06-30/#SECURITY-2371