CVE-2021-21317

Denial of Service in uap-core

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.

Categories

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.48% Top 20%
Third-Party Advisory github.com Third-Party Advisory npmjs.com
Affected: ua-parser uap-core
Published at:
Updated at:

References

Link Tags
https://github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4 third party advisory
https://github.com/ua-parser/uap-core/commit/dc9925d458214cfe87b93e35346980612f6ae96c patch
https://www.npmjs.com/package/uap-core third party advisory product

Frequently Asked Questions

What is the severity of CVE-2021-21317?
CVE-2021-21317 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21317?
To fix CVE-2021-21317, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21317 being actively exploited in the wild?
It is possible that CVE-2021-21317 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21317?
CVE-2021-21317 affects ua-parser uap-core.
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