{"id":"UBUNTU-CVE-2026-0992","details":"A flaw was found in the libxml2 library. This uncontrolled resource consumption vulnerability occurs when processing XML catalogs that contain repeated \u003cnextCatalog\u003e elements pointing to the same downstream catalog. A remote attacker can exploit this by supplying crafted catalogs, causing the parser to redundantly traverse catalog chains. This leads to excessive CPU consumption and degrades application availability, resulting in a denial-of-service condition.","modified":"2026-04-22T16:18:15.279011Z","published":"2026-01-15T15:15:00Z","related":["USN-7974-1"],"upstream":["CVE-2026-0992"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-0992"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-0992"},{"type":"REPORT","url":"https://access.redhat.com/security/cve/CVE-2026-0992"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-7974-1"}],"affected":[{"package":{"name":"libxml2","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/libxml2@2.9.1+dfsg1-3ubuntu4.13+esm11?arch=source&distro=esm-infra-legacy/trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.9.1+dfsg1-3ubuntu4.13+esm11"}]}],"versions":["2.9.1+dfsg1-3ubuntu2","2.9.1+dfsg1-3ubuntu3","2.9.1+dfsg1-3ubuntu4","2.9.1+dfsg1-3ubuntu4.1","2.9.1+dfsg1-3ubuntu4.2","2.9.1+dfsg1-3ubuntu4.3","2.9.1+dfsg1-3ubuntu4.4","2.9.1+dfsg1-3ubuntu4.5","2.9.1+dfsg1-3ubuntu4.6","2.9.1+dfsg1-3ubuntu4.7","2.9.1+dfsg1-3ubuntu4.8","2.9.1+dfsg1-3ubuntu4.9","2.9.1+dfsg1-3ubuntu4.10","2.9.1+dfsg1-3ubuntu4.11","2.9.1+dfsg1-3ubuntu4.12","2.9.1+dfsg1-3ubuntu4.13","2.9.1+dfsg1-3ubuntu4.13+esm1","2.9.1+dfsg1-3ubuntu4.13+esm2","2.9.1+dfsg1-3ubuntu4.13+esm3","2.9.1+dfsg1-3ubuntu4.13+esm4","2.9.1+dfsg1-3ubuntu4.13+esm5","2.9.1+dfsg1-3ubuntu4.13+esm6","2.9.1+dfsg1-3ubuntu4.13+esm7","2.9.1+dfsg1-3ubuntu4.13+esm8","2.9.1+dfsg1-3ubuntu4.13+esm9","2.9.1+dfsg1-3ubuntu4.13+esm10"],"ecosystem_specific":{"availability":"Available 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