Vulnerability identifier: #VU49528

Vulnerability risk: Medium

CVSSv3.1: 4.8 [CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-21605

CWE-ID: CWE-22

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 perform directory traversal attacks.

The vulnerability exists due to input validation error when processing directory traversal sequences in agent names. A remote authenticated attacker can choose agent names that cause Jenkins to override unrelated "config.xml" files.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Jenkins: 2.0 - 240

Jenkins LTS: 2.7.1 - 2.263.1

---

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

---

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.