CVSS 3.1
5.3 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LCVE-2021-21317
Medium (5.3) in uap-core project uap-core. EPSS 2.5% chance of exploitation in the next 30 days. Fixed in uap-core 0.11.0.
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.
Severity
- EPSS
- 2.5% chance of exploitation in the next 30 days; higher than 84% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-1333, CWE-400
- Published
- Modified
- Record from
- the NVD, synced
Affected
- uap-core_project:uap-core
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-p4pj-mg4r-x6v4 | npm | uap-core | <0.11.0 | 0.11.0 |
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