{"id":"CVE-2018-20843","details":"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).","modified":"2026-05-30T07:52:13.861237Z","published":"2019-06-24T17:15:09.980Z","related":["ALSA-2020:4846","SUSE-SU-2019:1834-1","SUSE-SU-2019:1835-1","openSUSE-SU-2019:1777-1","openSUSE-SU-2024:10748-1"],"database_specific":{"unresolved_ranges":[{"vendor_product":"oracle:hospitality_res_3700","extracted_events":[{"introduced":"5.7"},{"last_affected":"5.7.6"}],"source":"CPE_RANGE","cpes":["cpe:2.3:a:oracle:hospitality_res_3700:*:*:*:*:*:*:*:*"]},{"vendor_product":"tenable:nessus","extracted_events":[{"fixed":"8.15.0"}],"source":"CPE_RANGE","cpes":["cpe:2.3:a:tenable:nessus:*:*:*:*:*:*:*:*"]},{"vendor_product":"canonical:ubuntu_linux","extracted_events":[{"last_affected":"12.04"},{"last_affected":"14.04"},{"last_affected":"16.04"},{"last_affected":"18.04"},{"last_affected":"18.10"},{"last_affected":"19.04"}],"source":"CPE_STRING","cpes":["cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:-:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:*"]},{"vendor_product":"debian:debian_linux","extracted_events":[{"last_affected":"8.0"},{"last_affected":"9.0"}],"source":"CPE_STRING","cpes":["cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*","cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"]},{"vendor_product":"fedoraproject:fedora","extracted_events":[{"last_affected":"29"},{"last_affected":"30"}],"source":"CPE_STRING","cpes":["cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*","cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*"]},{"vendor_product":"opensuse:leap","extracted_events":[{"last_affected":"15.0"},{"last_affected":"15.1"}],"source":"CPE_STRING","cpes":["cpe:2.3:o:opensuse:leap:15.0:*:*:*:*:*:*:*","cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*"]},{"vendor_product":"oracle:http_server","extracted_events":[{"last_affected":"12.1.3.0"},{"last_affected":"12.2.1.4.0"}],"source":"CPE_STRING","cpes":["cpe:2.3:a:oracle:http_server:12.1.3.0:*:*:*:*:*:*:*","cpe:2.3:a:oracle:http_server:12.2.1.4.0:*:*:*:*:*:*:*"]},{"vendor_product":"oracle:outside_in_technology","extracted_events":[{"last_affected":"8.5.4"},{"last_affected":"8.5.5"}],"source":"CPE_STRING","cpes":["cpe:2.3:a:oracle:outside_in_technology:8.5.4:*:*:*:*:*:*:*","cpe:2.3:a:oracle:outside_in_technology:8.5.5:*:*:*:*:*:*:*"]}]},"references":[{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEJJSQSG3KSUQY4FPVHZ7ZTT7FORMFVD/"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IDAUGEB3TUP6NEKJDBUBZX7N5OAUOOOK/"},{"type":"ADVISORY","url":"http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00039.html"},{"type":"ADVISORY","url":"https://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changes"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2019/06/msg00028.html"},{"type":"ADVISORY","url":"https://seclists.org/bugtraq/2019/Jun/39"},{"type":"ADVISORY","url":"https://security.gentoo.org/glsa/201911-08"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20190703-0001/"},{"type":"ADVISORY","url":"https://support.f5.com/csp/article/K51011533"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/4040-1/"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/4040-2/"},{"type":"ADVISORY","url":"https://www.debian.org/security/2019/dsa-4472"},{"type":"ADVISORY","url":"https://www.tenable.com/security/tns-2021-11"},{"type":"REPORT","url":"https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226"},{"type":"FIX","url":"https://github.com/libexpat/libexpat/issues/186"},{"type":"FIX","url":"https://github.com/libexpat/libexpat/pull/262"},{"type":"FIX","url":"https://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpuApr2021.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpuapr2020.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpuoct2020.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpuoct2021.html"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/libexpat/libexpat","events":[{"introduced":"0"},{"fixed":"d3b78b42a2dcdea98e22625cfff67a49d47e6025"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"2.2.7"}],"source":"CPE_RANGE","cpe":"cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*"}}],"versions":["R_2_2_6","R_2_2_5","R_2_2_4","R_2_2_3","R_2_2_2","R_2_2_1","R_2_2_0","R_2_1_1","R_2_1_0","R_2_0_1","R_2_0_0","R_1_95_8","R_1_95_7","R_1_95_6","R_1_95_5","R_1_95_4","R_1_95_3","R_1_95_2","R_1_95_0","libexpat-alpha-1","start","sourceforge_init","jclark-orig","V20000512","V19991013","V19990728","V19990709","V19990626","V1_1","V19990425","V1990307","V19990109","V19981231","V19981122","V1_0","beta4","beta3","beta2","REC1_0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2018-20843.json","vanir_signatures_modified":"2026-05-30T07:52:13Z","vanir_signatures":[{"deprecated":false,"id":"CVE-2018-20843-74406d59","source":"https://github.com/libexpat/libexpat/commit/d3b78b42a2dcdea98e22625cfff67a49d47e6025","digest":{"length":670,"function_hash":"10718674393994758979083102855553023681"},"signature_version":"v1","signature_type":"Function","target":{"function":"START_TEST","file":"expat/tests/runtests.c"}},{"deprecated":false,"id":"CVE-2018-20843-ee80e572","source":"https://github.com/libexpat/libexpat/commit/d3b78b42a2dcdea98e22625cfff67a49d47e6025","digest":{"threshold":0.9,"line_hashes":["70970158302216444732948686873374648009","197734145770944038326200234670765972062","333002349092091346504095730741649465004","132190683235044997527211951942674695301"]},"signature_version":"v1","signature_type":"Line","target":{"file":"expat/tests/runtests.c"}}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}