vulnerability
Ubuntu: (CVE-2021-21317): uap-core vulnerability
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:N/AC:L/Au:N/C:N/I:N/A:P) | Feb 16, 2021 | Jun 26, 2025 | Mar 27, 2026 |
Severity
5
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:P)
Published
Feb 16, 2021
Added
Jun 26, 2025
Modified
Mar 27, 2026
Description
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.
Solution
no-fix-ubuntu-package
References
- CVE-2021-21317
- https://attackerkb.com/topics/CVE-2021-21317
- CWE-1333
- CWE-400
- EUVD-EUVD-2021-0561
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-0561
- https://github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4
- https://www.cve.org/CVERecord?id=CVE-2021-21317
- https://www.npmjs.com/package/uap-core
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