#VU60792 Double Free in Vim - CVE-2021-4173

Vulnerability identifier: #VU60792

Vulnerability risk: High

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-4173

CWE-ID: CWE-415

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Vim
Client/Desktop applications / Software for system administration

Vendor: Vim.org

Description

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

The vulnerability exists due to a boundary error. A remote attacker can trick the victim to open a specially crafted file, trigger double free error 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

Vim: 8.2.0 - 8.2.3901

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External links
https://huntr.dev/bounties/a1b236b9-89fb-4ccf-9689-ba11b471e766
https://github.com/vim/vim/commit/9c23f9bb5fe435b28245ba8ac65aa0ca6b902c04
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2EY2VFBU3YGGWI5BW4XKT3F37MYGEQUD/
https://www.openwall.com/lists/oss-security/2022/01/15/1
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3FH2J57GDA2WMBS6J56F6QQRA6BXQQFZ/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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