{"answers":{"affected":"It affects 9 products.","exploited":"There is no known exploitation of CVE-2018-20843 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2018-20843 is a high-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 24 Jun 2019. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2018-20843 and fix it if it is affected.\n\nWhat it is: CVE-2018-20843 is a high-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 24 Jun 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2018-20843 in the wild and no public exploit code.\n\nAffected product: Canonical Ubuntu Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2018-20843/ (Markdown: https://insights.sbomify.com/CVE-2018-20843/index.md)","id":"CVE-2018-20843","markdown":"https://insights.sbomify.com/CVE-2018-20843/index.md","name":"CVE-2018-20843","record":{"aliases":["ALPINE-CVE-2018-20843","ALSA-2020:4846","CLEANSTART-2026-ZY15804","DEBIAN-CVE-2018-20843","DLA-1839-1","DSA-4472-1","GHSA-hj5j-c8qp-mgmv","MGASA-2019-0274","RHSA-2020:4846","SUSE-SU-2019:1834-1","SUSE-SU-2019:1835-1","UBUNTU-CVE-2018-20843","USN-4040-1","USN-4040-2","openSUSE-SU-2019:1777-1"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"XML parsing library","requires_auth":"none","summary":"Attackers can cause denial of service by sending XML with many colons, exhausting resources in the Expat library.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"ubuntu_linux","vendor":"canonical"},{"product":"debian_linux","vendor":"debian"},{"product":"fedora","vendor":"fedoraproject"},{"product":"libexpat","vendor":"libexpat_project"},{"product":"leap","vendor":"opensuse"},{"product":"hospitality_res_3700","vendor":"oracle"},{"product":"http_server","vendor":"oracle"},{"product":"outside_in_technology","vendor":"oracle"},{"product":"nessus","vendor":"tenable"}],"cvss":{"score":7.5,"severity":"high","source":"cisa-adp","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-611","name":"Improper Restriction of XML External Entity Reference"}],"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).","ecosystems":["AlmaLinux:8","Red Hat:enterprise_linux:8::crb","SUSE:Linux Enterprise Desktop 12 SP4","SUSE:Linux Enterprise Module for Basesystem 15","SUSE:Linux Enterprise Module for Basesystem 15 SP1","SUSE:Linux Enterprise Server 12 SP4","SUSE:Linux Enterprise Server for SAP Applications 12 SP4","SUSE:Linux Enterprise Software Development Kit 12 SP4","openSUSE:Leap 15.0","openSUSE:Leap 15.1"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Denial of service in n/a","id":"CVE-2018-20843","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"canonical:ubuntu_linux","products":["canonical:ubuntu_linux","debian:debian_linux","fedoraproject:fedora","libexpat_project:libexpat","opensuse:leap","oracle:http_server","oracle:outside_in_technology","tenable:nessus"],"type":"denial_of_service","year":"2018"},"n_packages":15,"n_references":21,"next":{"headline":"Denial of service in n/a","id":"CVE-2018-20845"},"packages":[{"ecosystem":"AlmaLinux:8","fixed":["2.2.4-5.el8"],"introduced":["0"],"last_affected":[],"package":"mingw32-expat","purl":"pkg:rpm/almalinux/mingw32-expat","source":"ALSA-2020:4846"},{"ecosystem":"AlmaLinux:8","fixed":["2.2.4-5.el8"],"introduced":["0"],"last_affected":[],"package":"mingw64-expat","purl":"pkg:rpm/almalinux/mingw64-expat","source":"ALSA-2020:4846"},{"ecosystem":"Red Hat:enterprise_linux:8::crb","fixed":["0:2.2.4-5.el8"],"introduced":["0"],"last_affected":[],"package":"mingw-expat","purl":"pkg:rpm/redhat/mingw-expat","source":"RHSA-2020:4846"},{"ecosystem":"Red Hat:enterprise_linux:8::crb","fixed":["0:2.2.4-5.el8"],"introduced":["0"],"last_affected":[],"package":"mingw32-expat","purl":"pkg:rpm/redhat/mingw32-expat","source":"RHSA-2020:4846"},{"ecosystem":"Red Hat:enterprise_linux:8::crb","fixed":["0:2.2.4-5.el8"],"introduced":["0"],"last_affected":[],"package":"mingw32-expat-debuginfo","purl":"pkg:rpm/redhat/mingw32-expat-debuginfo","source":"RHSA-2020:4846"},{"ecosystem":"Red Hat:enterprise_linux:8::crb","fixed":["0:2.2.4-5.el8"],"introduced":["0"],"last_affected":[],"package":"mingw64-expat","purl":"pkg:rpm/redhat/mingw64-expat","source":"RHSA-2020:4846"},{"ecosystem":"Red Hat:enterprise_linux:8::crb","fixed":["0:2.2.4-5.el8"],"introduced":["0"],"last_affected":[],"package":"mingw64-expat-debuginfo","purl":"pkg:rpm/redhat/mingw64-expat-debuginfo","source":"RHSA-2020:4846"},{"ecosystem":"SUSE:Linux Enterprise Desktop 12 SP4","fixed":["2.1.0-21.6.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/suse/expat\u0026distro=SUSE%20Linux%20Enterprise%20Desktop%2012%20SP4","source":"SUSE-SU-2019:1834-1"},{"ecosystem":"SUSE:Linux Enterprise Module for Basesystem 15","fixed":["2.2.5-3.3.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/suse/expat\u0026distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015","source":"SUSE-SU-2019:1835-1"},{"ecosystem":"SUSE:Linux Enterprise Module for Basesystem 15 SP1","fixed":["2.2.5-3.3.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/suse/expat\u0026distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP1","source":"SUSE-SU-2019:1835-1"},{"ecosystem":"SUSE:Linux Enterprise Server 12 SP4","fixed":["2.1.0-21.6.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/suse/expat\u0026distro=SUSE%20Linux%20Enterprise%20Server%2012%20SP4","source":"SUSE-SU-2019:1834-1"},{"ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 12 SP4","fixed":["2.1.0-21.6.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/suse/expat\u0026distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2012%20SP4","source":"SUSE-SU-2019:1834-1"},{"ecosystem":"SUSE:Linux Enterprise Software Development Kit 12 SP4","fixed":["2.1.0-21.6.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/suse/expat\u0026distro=SUSE%20Linux%20Enterprise%20Software%20Development%20Kit%2012%20SP4","source":"SUSE-SU-2019:1834-1"},{"ecosystem":"openSUSE:Leap 15.0","fixed":["2.2.5-lp151.3.3.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/opensuse/expat\u0026distro=openSUSE%20Leap%2015.0","source":"openSUSE-SU-2019:1777-1"},{"ecosystem":"openSUSE:Leap 15.1","fixed":["2.2.5-lp151.3.3.1"],"introduced":["0"],"last_affected":[],"package":"expat","purl":"pkg:rpm/opensuse/expat\u0026distro=openSUSE%20Leap%2015.1","source":"openSUSE-SU-2019:1777-1"}],"prev":{"headline":"Command injection in n/a","id":"CVE-2018-20841"},"products":["n/a"],"published":"2019-06-24","related":[{"cvss_score":9.8,"headline":"SaltStack Salt Authentication Bypass","id":"CVE-2020-11651","kev_date_added":"2021-11-03","published":"2020-04-30"},{"cvss_score":9.8,"headline":"OpenSMTPD Remote Code Execution","id":"CVE-2020-7247","kev_date_added":"2022-03-25","published":"2020-01-29"},{"cvss_score":9.8,"headline":"Exim Out-of-bounds Write","id":"CVE-2019-16928","kev_date_added":"2022-03-03","published":"2019-09-27"},{"cvss_score":9.8,"headline":"Exim Buffer Overflow","id":"CVE-2018-6789","kev_date_added":"2021-11-03","published":"2018-02-08"},{"cvss_score":9.8,"headline":"Oracle Java SE and Java SE Embedded Remote Code Execution","id":"CVE-2015-2590","kev_date_added":"2022-03-03","published":"2015-07-16"},{"cvss_score":9.8,"headline":"Oracle JRE Remote Code Execution","id":"CVE-2013-0422","kev_date_added":"2022-05-25","published":"2013-01-10"},{"cvss_score":9.8,"headline":"Oracle Java SE Runtime Environment (JRE) Arbitrary Code Execution","id":"CVE-2011-3544","kev_date_added":"2022-03-03","published":"2011-10-19"}],"sources":[{"class":"attribution","licence":"MIT","name":"AlmaLinux","prefix":"ALSA"},{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Red Hat","prefix":"RHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"SUSE"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"openSUSE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-14","vendors":["n/a"]},"summary":"Attackers can cause denial of service by sending XML with many colons, exhausting resources in the Expat library.","url":"https://insights.sbomify.com/CVE-2018-20843/"}