Resource exhaustion in Ua-Parser Uap-Core
CVE-2021-21317
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.
Vulnerability class: DoS (Denial of Service)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.025 (84.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 84.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.025 · newest: 0.025 · change: 0.000
Affected products
- Ua-Parser Uap-Core — versions < 0.11.0
- Uap-Core Project
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4 (Third Party Advisory)
- github.com/ua-parser/uap-core/commit/dc9925d458214cfe87b93e35346980612f6ae96c (Patch)
- www.npmjs.com/package/uap-core (Product, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-21317?
- CVE-2021-21317 is a medium-severity vulnerability in Ua-Parser Uap-Core, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2021-02-16.
- How severe is CVE-2021-21317?
- Medium severity. CVSS v3 base score is 5.3 out of 10.
- Is CVE-2021-21317 known to be exploited?
- 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.