CVE-2021-21317
What it is
uap-core in an open-source npm package which contains the core of BrowserScope's original user agent string parser. In uap-core before version 0.11.0, some regexes are vulnerable to regular expression denial of service (REDoS) due to overlapping capture groups. This allows remote attackers to overload a server by setting the User-Agent header in an HTTP(S) request to maliciously crafted long strings. This is fixed in version 0.11.0. Downstream packages such as uap-python, uap-ruby etc which depend upon uap-core follow different version schemes.
At a glance
- Exploitability
- Can be exploited over the network without logging in. Limited direct impact.
- Exploit odds
- 2.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 2.5% in the next 30 days (EPSS).
- Severity: 5.3 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 2.5% · EPSS, next 30 days
- Weakness
- CWE-400 · Uncontrolled resource consumption
- Record status
- Modified
Affected
- uap-core Project uap-core < 0.11.0
Attack profile CVSS 3.1 · 5.3
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-21317.md and follow it. Check whether this project is affected by CVE-2021-21317. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/ua-parser/uap-core/commit/dc9925d458214cfe87b93e35346980612f6ae96c
- https://github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4
- https://github.com/ua-parser/uap-core/commit/dc9925d458214cfe87b93e35346980612f6ae96c
- https://github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4
References
- https://github.com/ua-parser/uap-core/commit/dc9925d458214cfe87b93e35346980612f6ae96c
- https://github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4
- https://www.npmjs.com/package/uap-core
- https://github.com/ua-parser/uap-core/commit/dc9925d458214cfe87b93e35346980612f6ae96c
- https://github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4
- https://www.npmjs.com/package/uap-core