rust: Improper Neutralization of Argument Delimiters in a Command
CVE-2024-43402 is a high-severity improper neutralization of argument delimiters in a command vulnerability in rust from Rust-lang, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 1.81.0 as the first without the flaw, so updating rust to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.74% chance of exploitation within 30 days, higher than 55% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update rust to 1.81.0 or a later version.
- Read the advisory on blog.rust-lang.org for workarounds and exact fixed builds.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.1 | High | CNA (github.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
Rust is a programming language. The fix for CVE-2024-24576, where `std::process::Command` incorrectly escaped arguments when invoking batch files on Windows, was incomplete. Prior to Rust version 1.81.0, it was possible to bypass the fix when the batch file name had trailing whitespace or periods (which are ignored and stripped by Windows). To determine whether to apply the `cmd.exe` escaping rules, the original fix for the vulnerability checked whether the command name ended with `.bat` or `.cmd`. At the time that seemed enough, as we refuse to invoke batch scripts with no file extension. Windows removes trailing whitespace and periods when parsing file paths. For example, `.bat. .` is interpreted by Windows as `.bat`, but the original fix didn't check for that. Affected users who are using Rust 1.77.2 or greater can remove the trailing whitespace (ASCII 0x20) and trailing periods (ASCII 0x2E) from the batch file name to bypass the incomplete fix and enable the mitigations. Users are affected if their code or one of their dependencies invoke a batch script on Windows with trailing whitespace or trailing periods in the name, and pass untrusted arguments to it. Rust 1.81.0 will update the standard library to apply the CVE-2024-24576 mitigations to all batch files invocations, regardless of the trailing chars in the file name.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Argument Delimiters in a Command
The product constructs a string for a command to be executed by a separate component in another control sphere, but it does not properly delimit the intended arguments, options, or switches within that command string.
How developers prevent this class of flaw
- Understand all the potential areas where untrusted inputs can enter your product: parameters or arguments, cookies, anything read from the network, environment variables, request headers as well as content, URL components, e-mail, files, databases, and any external systems that provide data to the application. Perform input validation at well-defined interfaces.
- Directly convert your input type into the expected data type, such as using a conversion function that translates a string into a number. After converting to the expected data type, ensure that the input's values fall within the expected range of allowable values and that multi-field consistencies are maintained.
- When exchanging data between components, ensure that both components are using the same character encoding. Ensure that the proper encoding is applied at each interface. Explicitly set the encoding you are using whenever the protocol allows you to do so.
More Improper Neutralization of Argument Delimiters in a Command vulnerabilities (CWE-88)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in rust
- 9.8 Critical severity
- 10.0 Critical severity
Recent Improper Neutralization of Argument Delimiters in a Command vulnerabilities
- 7.2 High severity
Mitel SIP Phones Argument Injection Exploited
- 9.9 Critical severity
- 9.8 Critical severity
- 8.8 High severity
- 8.8 High severity
- 7.8 High severity
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