#VU58684 Use-after-free in BusyBox - CVE-2021-42382

Vulnerability identifier: #VU58684

Vulnerability risk: Low

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-42382

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
BusyBox
Universal components / Libraries / Software for developers

Vendor: busybox.net

Description

The vulnerability allows a remote user to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in the "getvar_s" function. A remote administrator can execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

BusyBox: 1.26.0 - 1.33.1

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External links
https://jfrog.com/blog/unboxing-busybox-14-new-vulnerabilities-uncovered-by-claroty-and-jfrog/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6T2TURBYYJGBMQTTN2DSOAIQGP7WCPGV/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UQXGOGWBIYWOIVXJVRKHZR34UMEHQBXS/

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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