{"id":"UBUNTU-CVE-2026-33036","details":"fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. Versions 4.0.0-beta.3 through 5.5.5 contain a bypass vulnerability where numeric character references (&#NNN;, &#xHH;) and standard XML entities completely evade the entity expansion limits (e.g., maxTotalExpansions, maxExpandedLength) added to fix CVE-2026-26278, enabling XML entity expansion Denial of Service. The root cause is that replaceEntitiesValue() in OrderedObjParser.js only enforces expansion counting on DOCTYPE-defined entities while the lastEntities loop handling numeric/standard entities performs no counting at all. An attacker supplying 1M numeric entity references like A can force ~147MB of memory allocation and heavy CPU usage, potentially crashing the process—even when developers have configured strict limits. This issue has been fixed in version 5.5.6.","modified":"2026-05-20T16:25:23.541952854Z","published":"2026-03-20T06:16:00Z","upstream":["CVE-2026-33036"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-33036"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-33036"},{"type":"REPORT","url":"https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-8gc5-j5rx-235r"},{"type":"REPORT","url":"https://github.com/NaturalIntelligence/fast-xml-parser/commit/bd26122c838e6a55e7d7ac49b4ccc01a49999a01"},{"type":"REPORT","url":"https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.5.6"}],"affected":[{"package":{"name":"node-webfont","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/node-webfont?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["11.4.0+dfsg2+~cs35.7.26-7ubuntu1"],"ecosystem_specific":{"binaries":[{"binary_name":"node-webfont","binary_version":"11.4.0+dfsg2+~cs35.7.26-7ubuntu1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33036.json"}},{"package":{"name":"node-webfont","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/node-webfont?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["11.4.0+dfsg2+~cs35.7.26-10","11.4.0+dfsg2+~cs35.7.26-13ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"node-webfont","binary_version":"11.4.0+dfsg2+~cs35.7.26-13ubuntu2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33036.json"}},{"package":{"name":"node-webfont","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/node-webfont?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["11.4.0+dfsg2+~cs35.7.26-13ubuntu2","11.4.0+dfsg2+~cs35.7.26-14","11.4.0+dfsg2+~cs35.7.26-15","11.4.0+dfsg2+~cs35.7.26-16build1","11.4.0+dfsg2+~cs35.7.26-18"],"ecosystem_specific":{"binaries":[{"binary_name":"node-webfont","binary_version":"11.4.0+dfsg2+~cs35.7.26-18"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33036.json"}}],"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"},{"type":"Ubuntu","score":"medium"}]}