CVE-2018-20843

Public Exploit

Description

In libexpat in Expat before 2.2.7, XML input including XML names that contain a large number of colons could make the XML parser consume a high amount of RAM and CPU resources while processing (enough to be usable for denial-of-service attacks).

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 5.82% Top 10%
Vendor Advisory ubuntu.com Vendor Advisory ubuntu.com Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory opensuse.org Vendor Advisory gentoo.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://usn.ubuntu.com/4040-1/ third party advisory vendor advisory
https://usn.ubuntu.com/4040-2/ third party advisory vendor advisory
https://www.debian.org/security/2019/dsa-4472 third party advisory vendor advisory
https://seclists.org/bugtraq/2019/Jun/39 third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2019/06/msg00028.html third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEJJSQSG3KSUQY4FPVHZ7ZTT7FORMFVD/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IDAUGEB3TUP6NEKJDBUBZX7N5OAUOOOK/ vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00039.html third party advisory vendor advisory mailing list
https://security.gentoo.org/glsa/201911-08 third party advisory vendor advisory
https://www.oracle.com/security-alerts/cpuapr2020.html third party advisory patch
https://www.oracle.com/security-alerts/cpuoct2020.html third party advisory patch
https://github.com/libexpat/libexpat/issues/186 third party advisory patch issue tracking
https://github.com/libexpat/libexpat/pull/262 third party advisory exploit patch
https://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6 third party advisory patch
https://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changes third party advisory release notes
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226 third party advisory issue tracking
https://security.netapp.com/advisory/ntap-20190703-0001/ third party advisory
https://support.f5.com/csp/article/K51011533 third party advisory
https://www.oracle.com/security-alerts/cpuApr2021.html third party advisory patch
https://www.oracle.com/security-alerts/cpuoct2021.html third party advisory patch
https://www.tenable.com/security/tns-2021-11 third party advisory

Frequently Asked Questions

What is the severity of CVE-2018-20843?
CVE-2018-20843 has been scored as a high severity vulnerability.
How to fix CVE-2018-20843?
To fix CVE-2018-20843, 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-2018-20843 being actively exploited in the wild?
It is possible that CVE-2018-20843 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~6% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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