CVE-2018-20843

high-risk

Published 2019-06-24

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).

Do I need to act?

5.6% chance of exploitation in next 30 days

EPSS score — moderate exploit probability

Not on CISA KEV list

No confirmed active exploitation reported to CISA

Patch status unknown

Check vendor advisories for fix availability and mitigation guidance

CVSS 7.5/10 High

NETWORK / LOW complexity

Affected Products (19)

Libexpat

Ubuntu Linux

Debian Linux

Fedora

Leap

Hospitality Res 3700

Http Server

Outside In Technology

Nessus

Affected Vendors

Debian Oracle Canonical Fedoraproject Opensuse Libexpat Project Tenable

References (42)

Mailing List http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00039.html

Issue Tracking https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226

Release Notes https://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changes

Issue Tracking https://github.com/libexpat/libexpat/issues/186

Exploit https://github.com/libexpat/libexpat/pull/262

Patch https://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760...

Mailing List https://lists.debian.org/debian-lts-announce/2019/06/msg00028.html

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro...

Mailing List https://seclists.org/bugtraq/2019/Jun/39

Third Party Advisory https://security.gentoo.org/glsa/201911-08

Third Party Advisory https://security.netapp.com/advisory/ntap-20190703-0001/

Third Party Advisory https://support.f5.com/csp/article/K51011533

Third Party Advisory https://usn.ubuntu.com/4040-1/

Third Party Advisory https://usn.ubuntu.com/4040-2/

Third Party Advisory https://www.debian.org/security/2019/dsa-4472

Patch https://www.oracle.com/security-alerts/cpuApr2021.html

Patch https://www.oracle.com/security-alerts/cpuapr2020.html

Patch https://www.oracle.com/security-alerts/cpuoct2020.html

Patch https://www.oracle.com/security-alerts/cpuoct2021.html

and 22 more references

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high-risk

Severity 26/34 · High

Exploitability 8/34 · Low

Exposure 19/34 · Moderate