#VU59053 Code Injection in Logback - CVE-2021-42550

Vulnerability identifier: #VU59053

Vulnerability risk: Medium

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:Green]

CVE-ID: CVE-2021-42550

CWE-ID: CWE-94

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Logback
Server applications / Other server solutions

Vendor: QOS.ch

Description

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

The vulnerability exists due to improper input validation. A remote user can send a specially crafted request to the application and execute arbitrary code on the target system by tricking the application to load a malicious configuration from a remote LDAP server.

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

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Logback: 1.2.0 - 1.3.0 alpha10

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External links
http://github.com/cn-panda/logbackRceDemo
http://jira.qos.ch/browse/LOGBACK-1591
http://logback.qos.ch/news.html

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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.