Summary
Multiple issues involving quote API in shlex
Issue 1: Failure to quote characters
Affected versions of this crate allowed the bytes { and \xa0 to appear unquoted and unescaped in command arguments.
If the output of quote or join is passed to a shell, then what should be a single command argument could be interpreted as multiple arguments.
This does not directly allow arbitrary command execution (you can't inject a command substitution or similar). But depending on the command you're running, being able to inject multiple arguments where only one is expected could lead to undesired consequences, potentially including arbitrary command execution.
The flaw was corrected in version 1.2.1 by escaping additional characters. Updating to 1.3.0 is recommended, but 1.2.1 offers a more minimal fix if desired.
Workaround: Check for the bytes { and \xa0 in quote/join input or output.
(Note: { is problematic because it is used for glob expansion. \xa0 is problematic because it's treated as a word separator in specific environments.)
Issue 2: Dangerous API w.r.t. nul bytes
Version 1.3.0 deprecates the quote and join APIs in favor of try_quote and try_join, which behave the same except that they have Result return type, returning Err if the input contains nul bytes.
Strings containing nul bytes generally cannot be used in Unix command arguments or environment variables, and most shells cannot handle nul bytes even internally. If you try to pass one anyway, then the results might be security-sensitive in uncommon scenarios. More details here.
Due to the low severity, the behavior of the original quote and join APIs has not changed; they continue to allow nuls.
Workaround: Manually check for nul bytes in quote/join input or output.
Issue 3: Lack of documentation for interactive shell risks
The quote family of functions does not and cannot escape control characters. With non-interactive shells this is perfectly safe, as control characters have no special effect. But if you writing directly to the standard input of an interactive shell (or through a pty), then control characters can cause misbehavior including arbitrary command injection.
This is essentially unfixable, and has not been patched. But as of version 1.3.0, documentation has been added.
Future versions of shlex may add API variants that avoid the issue at the cost of reduced portability.
Impact
CVE-2024-58266 has a CVSS score of 3.2 (Low). The vector is requires local access, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.3.0); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2024-58266? CVE-2024-58266 is a low-severity security vulnerability in shlex (rust), affecting versions < 1.3.0. It is fixed in 1.3.0.
- How severe is CVE-2024-58266? CVE-2024-58266 has a CVSS score of 3.2 (Low). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of shlex are affected by CVE-2024-58266? shlex (rust) versions < 1.3.0 is affected.
- Is there a fix for CVE-2024-58266? Yes. CVE-2024-58266 is fixed in 1.3.0. Upgrade to this version or later.
- Is CVE-2024-58266 exploitable, and should I be worried? Whether CVE-2024-58266 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2024-58266 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2024-58266? Upgrade
shlexto 1.3.0 or later.