Quick answers
- Is CVE-2021-21384 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2021-21384 being exploited in the wild.
- How severe is CVE-2021-21384?
- Low severity, with a CVSS score of 3.1, published 18 March 2021.
- Which products and versions are affected?
- shescape (npm) SEMVER:introduced=0,fixed=1.1.3.
- Is there a fix for CVE-2021-21384?
- Yes. shescape (npm): upgrade to 1.1.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2021-21384 attacked?
- It is attacked with local access, in a software library.
- Am I affected by CVE-2021-21384?
- Check whether you run shescape (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- shescape (npm): upgrade to 1.1.3 or later
npm install shescape@1.1.3
Technical details
The vulnerability is an incomplete input sanitization flaw in Shescape's quote() function (CWE-88). The library failed to escape null characters (\x00) in shell command arguments, allowing them to pass through to the shell unfiltered. An attacker who can control user input can inject a null byte followed by arbitrary shell commands. The vulnerability affects all versions prior to 1.1.3, is network-reachable if the application processes untrusted input, and allows command execution depending on application context and shell behavior. The patch in v1.1.3 properly escapes null characters.
Affected products
- Eric Cornelissen Shescape < 1.1.3
Identifiers
- CVE-2021-21384
- GHSA-f2rp-38vg-j3gh
Timeline
- 2021-03-13: disclosed
- 2021-03-18: patched: v1.1.3 released