CVE-2018-20164

Name: CVE-2018-20164
Creator: NVD / NIST
Published: 2019-02-13T14:29:00.24+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 3.30%

Last modified Jun 17, 2026

CVE-2018-20164 is a vulnerability of currently unknown severity. An issue was discovered in regex.yaml (aka regexes.yaml) in UA-Parser UAP-Core before 0.6.0. A Regular Expression Denial of Service (ReDoS) issue allows remote attackers to overload a server by setting the User-Agent header in an HTTP(S) request to a value containing a long digit string. EPSS estimates a 3.30% chance of exploitation in the next 30 days.

Description

An issue was discovered in regex.yaml (aka regexes.yaml) in UA-Parser UAP-Core before 0.6.0. A Regular Expression Denial of Service (ReDoS) issue allows remote attackers to overload a server by setting the User-Agent header in an HTTP(S) request to a value containing a long digit string. (The UAP-Core project contains the vulnerability, propagating to all implementations.)

Metrics

EPSS Probability

3.30%

86.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-185

Affected Software

Vendor	Product	Versions
Uaparser	User Agent Parser-Core	< 0.6.0

References

https://github.com/ua-parser/uap-core/commit/010ccdc7303546cd22b9da687c29f4a996990014Patch, Third Party Advisory
https://github.com/ua-parser/uap-core/commit/156f7e12b215bddbaf3df4514c399d683e6cdadcPatch, Third Party Advisory
https://github.com/ua-parser/uap-core/issues/332
https://www.x41-dsec.de/lab/advisories/x41-2018-009-uaparser/Exploit, Third Party Advisory
https://github.com/ua-parser/uap-core/commit/010ccdc7303546cd22b9da687c29f4a996990014Patch, Third Party Advisory
https://github.com/ua-parser/uap-core/commit/156f7e12b215bddbaf3df4514c399d683e6cdadcPatch, Third Party Advisory
https://github.com/ua-parser/uap-core/issues/332
https://www.x41-dsec.de/lab/advisories/x41-2018-009-uaparser/Exploit, Third Party Advisory

Timeline

Published: Feb 13, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-20164?

How severe is CVE-2018-20164?

Severity scoring for CVE-2018-20164 is pending analysis. The EPSS model estimates a 3.30% probability of exploitation in the next 30 days.

How do I fix CVE-2018-20164?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-20164?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST