CVE-2018-20843

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

7.11% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 93.7% of scored records. A rank, not a probability.

NVD base score

7.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2019-06-24 16:06Z7 YR AGO

Last updated

2025-05-30 19:39Z1 YR AGO

Reserved

2019-06-24

Assigning CNA

mitre

Record state

PUBLISHED

Severity

High (CVSS 7.5)

CNA CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses

• CWE-611Improper Restriction of XML External Entity ReferenceBase
• CWE-400Uncontrolled Resource ConsumptionClass

Data version

5.1

Document digest

034be329eacfda974b94c11d09cf5b491608b77c33a98983ab8ba10a79fa15a0

• usn.ubuntu.comUSN-4040-1https://usn.ubuntu.com/4040-1/vendor-advisoryx_refsource_UBUNTU
• usn.ubuntu.comUSN-4040-2https://usn.ubuntu.com/4040-2/vendor-advisoryx_refsource_UBUNTU
• www.debian.orgDSA-4472https://www.debian.org/security/2019/dsa-4472vendor-advisoryx_refsource_DEBIAN
• seclists.org20190628 [SECURITY] [DSA 4472-1] expat security updatehttps://seclists.org/bugtraq/2019/Jun/39mailing-listx_refsource_BUGTRAQ
• lists.debian.org[debian-lts-announce] 20190629 [SECURITY] [DLA 1839-1] expat security updatehttps://lists.debian.org/debian-lts-announce/2019/06/msg00028.htmlmailing-listx_refsource_MLIST
• lists.fedoraproject.orgFEDORA-2019-18868e1715https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEJJSQSG3KSUQY4FPVHZ7ZTT7FORMFVD/vendor-advisoryx_refsource_FEDORA
• lists.fedoraproject.orgFEDORA-2019-139fcda84dhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IDAUGEB3TUP6NEKJDBUBZX7N5OAUOOOK/vendor-advisoryx_refsource_FEDORA
• lists.opensuse.orgopenSUSE-SU-2019:1777http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00039.htmlvendor-advisoryx_refsource_SUSE
• security.gentoo.orgGLSA-201911-08https://security.gentoo.org/glsa/201911-08vendor-advisoryx_refsource_GENTOO
• www.oracle.comhttps://www.oracle.com/security-alerts/cpuapr2020.htmlx_refsource_MISC
• www.oracle.comhttps://www.oracle.com/security-alerts/cpuoct2020.htmlx_refsource_MISC
• github.comhttps://github.com/libexpat/libexpat/issues/186x_refsource_MISC
• github.comhttps://github.com/libexpat/libexpat/pull/262x_refsource_MISC
• github.comhttps://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6x_refsource_MISC
• github.comhttps://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changesx_refsource_MISC
• bugs.chromium.orghttps://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226x_refsource_MISC
• security.netapp.comhttps://security.netapp.com/advisory/ntap-20190703-0001/x_refsource_CONFIRM
• support.f5.comhttps://support.f5.com/csp/article/K51011533x_refsource_CONFIRM
• www.oracle.comhttps://www.oracle.com/security-alerts/cpuApr2021.htmlx_refsource_MISC
• www.oracle.comhttps://www.oracle.com/security-alerts/cpuoct2021.htmlx_refsource_MISC
• www.tenable.comhttps://www.tenable.com/security/tns-2021-11x_refsource_CONFIRM