#VU49527 Information disclosure in Jenkins and Jenkins LTS - CVE-2021-21602

Vulnerability identifier: #VU49527

Vulnerability risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-21602

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Jenkins
Server applications / Application servers
Jenkins LTS
Server applications / Application servers

Vendor: Jenkins

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application in workspace browsers. A remote authenticated attacker can create symbolic links that allow them to access files outside workspaces using the workspace browser.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Jenkins: 2.0 - 240

Jenkins LTS: 2.7.1 - 2.263.1

---

External links
https://www.jenkins.io/security/advisory/2021-01-13/#SECURITY-1452

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.