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CVE-2020-5243
Denial of Service in uap-core when processing crafted User-Agent strings
Medium5.7EPSS 2.3%
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
uap-core before 0.7.3 is vulnerable to a denial of service attack when processing crafted User-Agent strings. 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 has been patched in uap-core 0.7.3.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 2.3% · top 17% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.7.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- RubyGemsuser_agent_parserGHSA-cmcx-xhr8-3w9p (opens in a new tab)
- npmuap-coreGHSA-cmcx-xhr8-3w9p (opens in a new tab)
References (2)
- https://github.com/ua-parser/uap-core/security/advisories/GHSA-cmcx-xhr8-3w9p (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/ua-parser/uap-core/commit/0afd61ed85396a3b5316f18bfd1edfaadf8e88e1 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-cmcx-xhr8-3w9p (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-5243)Record last updated .