High 7.5Published Jun 24, 2019

CVE-2018-20843In 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 (enoug…

Updated under an hour ago (2026-10-19 08:50 UTC)

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It affects Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP and 11 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-611
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mitre
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
libexpat_project libexpat libexpat_project:libexpat	before 2.2.7	NVD
canonical ubuntu_linux canonical:ubuntu_linux	12.04; 14.04; 16.04; 18.04; 18.10; 19.04	NVD
debian debian_linux debian:debian_linux	8.0; 9.0	NVD
fedoraproject fedora fedoraproject:fedora	29; 30	NVD
opensuse leap opensuse:leap	15.0; 15.1	NVD
oracle hospitality_res_3700 oracle:hospitality_res_3700	from 5.7 through 5.7.6	NVD
oracle http_server oracle:http_server	12.1.3.0; 12.2.1.4.0	NVD
oracle outside_in_technology oracle:outside_in_technology	8.5.4; 8.5.5	NVD
tenable nessus tenable:nessus	before 8.15.0	NVD

References

https://usn.ubuntu.com/4040-1/vendor-advisory, x-refsource-ubuntu, third-party-advisory
https://usn.ubuntu.com/4040-2/vendor-advisory, x-refsource-ubuntu, third-party-advisory
https://www.debian.org/security/2019/dsa-4472vendor-advisory, x-refsource-debian, third-party-advisory
https://seclists.org/bugtraq/2019/Jun/39mailing-list, x-refsource-bugtraq, third-party-advisory
https://lists.debian.org/debian-lts-announce/2019/06/msg00028.htmlmailing-list, x-refsource-mlist, third-party-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEJJSQSG3KSUQY4FPVHZ7ZTT7FORMFVD/vendor-advisory, x-refsource-fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IDAUGEB3TUP6NEKJDBUBZX7N5OAUOOOK/vendor-advisory, x-refsource-fedora
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00039.htmlvendor-advisory, x-refsource-suse, mailing-list, third-party-advisory
https://security.gentoo.org/glsa/201911-08vendor-advisory, x-refsource-gentoo, third-party-advisory
https://www.oracle.com/security-alerts/cpuapr2020.htmlx-refsource-misc, patch, third-party-advisory
https://www.oracle.com/security-alerts/cpuoct2020.htmlx-refsource-misc, patch, third-party-advisory
https://github.com/libexpat/libexpat/issues/186x-refsource-misc, issue-tracking, patch, third-party-advisory
https://github.com/libexpat/libexpat/pull/262x-refsource-misc, exploit, patch, third-party-advisory
https://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6x-refsource-misc, patch, third-party-advisory
https://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changesx-refsource-misc, release-notes, third-party-advisory
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226x-refsource-misc, issue-tracking, third-party-advisory
https://security.netapp.com/advisory/ntap-20190703-0001/x-refsource-confirm, third-party-advisory
https://support.f5.com/csp/article/K51011533x-refsource-confirm, third-party-advisory
https://www.oracle.com/security-alerts/cpuApr2021.htmlx-refsource-misc, patch, third-party-advisory
https://www.oracle.com/security-alerts/cpuoct2021.htmlx-refsource-misc, patch, third-party-advisory
https://www.tenable.com/security/tns-2021-11x-refsource-confirm, third-party-advisory
https://cert-portal.siemens.com/productcert/html/ssa-398330.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.