#VU26996 Deserialization of Untrusted Data in Yaml Axis - CVE-2020-2179

Vulnerability identifier: #VU26996

Vulnerability risk: High

CVSSv4.0: 6.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2020-2179

CWE-ID: CWE-502

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Yaml Axis
Web applications / Modules and components for CMS

Vendor: Jenkins

Description

The vulnerability allows a remote user to execute arbitrary code on the target system.

The vulnerability exists due to the affected software does not configure its YAML parser to prevent the instantiation of arbitrary types. A remote user able to configure a multi-configuration (Matrix) job, or control the contents of a previously configured job’s SCM repository can pass specially crafted data to the application and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Yaml Axis: 0.1.0 - 0.2.0

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External links
https://www.openwall.com/lists/oss-security/2020/04/16/4
https://jenkins.io/security/advisory/2020-04-16/#SECURITY-1825

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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.