Sudo up to 1.9.12.p1 Environment Variable SUDO_EDITOR/VISUAL/EDITOR protection mechanism

Summaryinfo

A vulnerability categorized as critical has been discovered in Sudo up to 1.9.12.p1. The impacted element is an unknown function of the component Environment Variable Handler. The manipulation of the argument SUDO_EDITOR/VISUAL/EDITOR results in protection mechanism. This vulnerability is known as CVE-2023-22809. It is possible to launch the attack remotely. Furthermore, an exploit is available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Sudo up to 1.9.12.p1 (Operating System Utility Software). It has been classified as critical. Affected is an unknown functionality of the component Environment Variable Handler. The manipulation of the argument SUDO_EDITOR/VISUAL/EDITOR with an unknown input leads to a protection mechanism vulnerability. CWE is classifying the issue as CWE-693. The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In Sudo before 1.9.12p2, the sudoedit (aka -e) feature mishandles extra arguments passed in the user-provided environment variables (SUDO_EDITOR, VISUAL, and EDITOR), allowing a local attacker to append arbitrary entries to the list of files to process. This can lead to privilege escalation. Affected versions are 1.8.0 through 1.9.12.p1. The problem exists because a user-specified editor may contain a "--" argument that defeats a protection mechanism, e.g., an EDITOR='vim -- /path/to/extra/file' value.

The weakness was published 01/18/2023. The advisory is shared for download at sudo.ws. This vulnerability is traded as CVE-2023-22809 since 01/06/2023. Technical details and a public exploit are known.

A public exploit has been developed by n3m1.sys in Bash. The exploit is shared for download at github.com. It is declared as proof-of-concept. As 0-day the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 240017 (TencentOS Server 3: sudo (TSSA-2023:0015)), which helps to determine the existence of the flaw in a target environment.

Applying the patch 1.9.12p2 is able to eliminate this problem.

The vulnerability is also documented in the databases at Exploit-DB (51217) and Tenable (240017). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System Utility Software

Name

• Sudo

Version

• 1.9.12.p1

License

• open-source

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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Once again VulDB remains the best source for vulnerability data.

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