CVE Vulnerabilities

CVE-2022-21658

Race Condition Enabling Link Following

Published: Jan 20, 2022 | Modified: Nov 07, 2023
CVSS 3.x
6.3
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H
CVSS 2.x
3.3 LOW
AV:L/AC:M/Au:N/C:N/I:P/A:P
RedHat/V2
RedHat/V3
5.3 MODERATE
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
Ubuntu
MEDIUM

Rust is a multi-paradigm, general-purpose programming language designed for performance and safety, especially safe concurrency. The Rust Security Response WG was notified that the std::fs::remove_dir_all standard library function is vulnerable a race condition enabling symlink following (CWE-363). An attacker could use this security issue to trick a privileged program into deleting files and directories the attacker couldnt otherwise access or delete. Rust 1.0.0 through Rust 1.58.0 is affected by this vulnerability with 1.58.1 containing a patch. Note that the following build targets dont have usable APIs to properly mitigate the attack, and are thus still vulnerable even with a patched toolchain: macOS before version 10.10 (Yosemite) and REDOX. We recommend everyone to update to Rust 1.58.1 as soon as possible, especially people developing programs expected to run in privileged contexts (including system daemons and setuid binaries), as those have the highest risk of being affected by this. Note that adding checks in your codebase before calling remove_dir_all will not mitigate the vulnerability, as they would also be vulnerable to race conditions like remove_dir_all itself. The existing mitigation is working as intended outside of race conditions.

Weakness

The product checks the status of a file or directory before accessing it, which produces a race condition in which the file can be replaced with a link before the access is performed, causing the product to access the wrong file.

Affected Software

Name Vendor Start Version End Version
Rust Rust-lang 1.0.0 (including) 1.58.0 (including)
Red Hat Enterprise Linux 8 RedHat rust-toolset:rhel8-8060020220125235043.eab6f2ea *
Rustc Ubuntu bionic *
Rustc Ubuntu esm-apps/xenial *
Rustc Ubuntu focal *
Rustc Ubuntu hirsute *
Rustc Ubuntu impish *
Rustc Ubuntu trusty/esm *
Rustc Ubuntu upstream *

References