CVE-2018-20843 — XML External Entity (XXE) Injection in Project Libexpat

CWE-611 — XML External Entity (XXE) InjectionCWE-400 — Uncontrolled Resource Consumption21 documents10 sources
Severity
7.5HIGHNVD
OSV5.0
EPSS
5.6%
top 9.68%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
9
Libexpat Project LibexpatTenable NessusOracle Hospitality RES 3700+6 more
Timeline
PublishedJun 24
Latest updateJan 13

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).

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 3.9 | Impact: 3.6

Affected Packages6 packages

▶NVDtenable/nessus< 8.15.0
▶NVDoracle/hospitality_res_37005.7 — 5.7.6
▶NVDopensuse/leap15.0, 15.1+1
▶NVDoracle/http_server12.1.3.0, 12.2.1.4.0+1

Also affects: Debian Linux 8.0, 9.0, Fedora 29, 30, Ubuntu Linux 12.04, 14.04, 16.04, 18.04, 18.10, 19.04

Patches

Patch: github.com ↗Patch: github.com ↗Patch: github.com ↗

🔴Vulnerability Details

5
OSV
libxmltok vulnerabilities↗2025-01-13
▶
OSV
libxmltok vulnerabilities↗2022-07-19
▶
GHSA
GHSA-hj5j-c8qp-mgmv: In libexpat in Expat before 2↗2022-05-24
▶
CVEList
CVE-2018-20843: In libexpat in Expat before 2↗2019-06-24
▶
OSV
CVE-2018-20843: In libexpat in Expat before 2↗2019-06-24
▶

📋Vendor Advisories

11
Ubuntu
xmltok library vulnerabilities↗2025-01-13
▶
Ubuntu
xmltok library vulnerabilities↗2022-07-19
▶
Oracle
Oracle Oracle Fusion Middleware Risk Matrix: SSL Module (LibExpat) — CVE-2018-20843↗2021-10-15
▶
Oracle
Oracle Oracle Food and Beverage Applications Risk Matrix: Common (LibExpat) — CVE-2018-20843↗2021-04-15
▶
Ubuntu
VTK vulnerabilities↗2021-03-15
▶

💬Community

4
Bugzilla
CVE-2018-20843 mingw-expat: expat: large number of colons in input makes parser consume high amount of resources, leading to DoS [fedora-all]↗2019-06-25
▶
Bugzilla
CVE-2018-20843 expat: large number of colons in input makes parser consume high amount of resources, leading to DoS↗2019-06-25
▶
Bugzilla
CVE-2018-20843 expat: large number of colons in input makes parser consume high amount of resources, leading to DoS [fedora-all]↗2019-06-25
▶
Bugzilla
CVE-2018-20843 mingw-expat: expat: large number of colons in input makes parser consume high amount of resources, leading to DoS [epel-7]↗2019-06-25
▶
CVE-2018-20843 — XML External Entity (XXE) Injection | cvebase