CVE-2022-24999: qs before 6.10.3, as used in Express before 4.17.3 and other products, allows attackers to cause a Node process hang for an Express application because an __ proto__ key can be used. In many typical Express use cases, an unauthenticated remote attacker can place the attack payload in the query string of the URL that is used to visit the application, such as a[__proto__]=b&a[__proto__]&a[length]=100000000. The fix was backported to qs 6.9.7, 6.8.3, 6.7.3, 6.6.1, 6.5.3, 6.4.1, 6.3.3, and 6.2.4 (and therefore Express 4.17.3, which has "deps: qs@6.9.7" in its release description, is not vulnerable).
Overview
- Severity
- High (CVSS 7.5)
- CVSS Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Exploit Status
- Not Exploited
- Patch Tuesday
- 2022-Nov
- Released
- 2025-09-03
- Last Updated
- 2026-02-18
- EPSS Score
- 1.54% (percentile: 81.4%)
FAQ
Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Detection & Weaponization (1 sources)
Maturity: Exploit
- GitHub PoC: 1 repositories
Affected Products (1)
Other
Revision History
- 2025-09-03: Information published.
- 2026-02-18: Information published.