CVE-2021-21317

MEDIUM

Uap-core < 0.11.0 - Denial of Service

Title source: rule
STIX 2.1

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.

References (3)

Core 3

Scores

CVSS v3 5.3
EPSS 0.0148
EPSS Percentile 81.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Details

CWE
CWE-1333 CWE-400
Status published
Products (2)
npm/uap-core 0 - 0.11.0npm
uap-core_project/uap-core < 0.11.0
Published Feb 16, 2021
Tracked Since Feb 18, 2026