Vulnerability identifier: #VU57989

Vulnerability risk: Medium

CVSSv3.1: 7.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-21696

CWE-ID: CWE-693

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 bypass implemented security restrictions.

The vulnerability exists due to the affected application does not limit agent read/write access to the libs/ directory inside build directories when using the FilePath APIs. A remote authenticated attacker can replace the code of a trusted library with a modified variant and execute arbitrary code on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Jenkins: 2.0 - 2.318

Jenkins LTS: 1.409.1 - 2.303.2

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External links
http://jenkins.io/security/advisory/2021-11-04/

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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.