CVE-2020-5243

Public Exploit
Denial of Service in uap-core when processing crafted User-Agent strings

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.

Categories

5.7
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.80% Top 30%
Third-Party Advisory github.com
Affected: ua-parser uap-core
Published at:
Updated at:

References

Link Tags
https://github.com/ua-parser/uap-core/security/advisories/GHSA-cmcx-xhr8-3w9p third party advisory exploit
https://github.com/ua-parser/uap-core/commit/0afd61ed85396a3b5316f18bfd1edfaadf8e88e1 patch

Frequently Asked Questions

What is the severity of CVE-2020-5243?
CVE-2020-5243 has been scored as a medium severity vulnerability.
How to fix CVE-2020-5243?
To fix CVE-2020-5243, 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-2020-5243 being actively exploited in the wild?
It is possible that CVE-2020-5243 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-2020-5243?
CVE-2020-5243 affects ua-parser uap-core.
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