{"id":"CVE-2026-44665","aliases":["EUVD-2026-30053","GHSA-5wm8-gmm8-39j9","ROOT-APP-NPM-CVE-2026-44665"],"status":"published","title":"fast-xml-builder: Attribute values with unwanted quotes can bypass malicious or unwanted attributes","description":"fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.","severity":{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00236,"percentile":0.14751,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-611","CWE-91"],"published":"2026-05-08T16:29:10Z","modified":"2026-10-28T02:30:28Z","fixes":[{"ecosystem":"npm","package":"fast-xml-builder","fixed_in":["1.1.7"],"sources":["ghsa","osv"]},{"ecosystem":"Root:npm","package":"@rootio/fast-xml-builder","fixed_in":["1.1.5-root.io.1","1.1.4-root.io.1","1.1.4-root.io.2","1.1.5-root.io.2","1.1.5-root.io.3"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"fast-xml-builder","fixed_in":["1.1.4-aikido.2","1.1.5-aikido.2","1.1.5-aikido.3"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"fast-xml-builder","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"1.1.6"},{"fixed":"1.1.7"}]}]},{"source":"osv","ecosystem":"npm","package":"fast-xml-builder","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.1.7"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"@rootio/fast-xml-builder","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.1.5-root.io.1"},{"fixed":"1.1.4-root.io.1"},{"fixed":"1.1.4-root.io.2"},{"fixed":"1.1.5-root.io.2"},{"fixed":"1.1.5-root.io.3"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"fast-xml-builder","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.1.4-aikido.2"},{"fixed":"1.1.5-aikido.2"},{"fixed":"1.1.5-aikido.3"}]}]}],"products":[{"vendor":"naturalintelligence","product":"fast-xml-builder"}],"references":[{"url":"https://github.com/NaturalIntelligence/fast-xml-builder/security/advisories/GHSA-5wm8-gmm8-39j9","tags":["x_refsource_CONFIRM","exploit","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44665","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-5wm8-gmm8-39j9"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44665.json","tags":["advisory"]},{"url":"https://github.com/NaturalIntelligence/fast-xml-builder","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-44665","title":"fast-xml-builder: Attribute values with unwanted quotes can bypass malicious or unwanted attributes","description":"fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.","status":"published","published":"2026-05-13T15:24:54.596Z","modified":"2026-05-18T15:04:53.679Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-91"],"updated_at":"2026-11-02T13:43:00.288193Z"}],"euvd":[{"id":"EUVD-2026-30053","description":"fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.","status":"published","published":"2026-05-13T15:24:54Z","modified":"2026-05-18T15:04:53Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T18:21:16.184545Z"}],"ghsa":[{"id":"GHSA-5wm8-gmm8-39j9","title":"fast-xml-builder allows attribute values with unwanted quotes to bypass malicious or unwanted attributes","description":"# Summary\nWhen an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML.\n\n## Detail\n\nMalicious Input\n```\n{\n      a: {\n        \"@_attr\": '\" onClick=\"alert(1)'\n      }\n}\n```\n\nOutput\n```xml\n\u003ca attr=\"\" onClick=\"alert(1)\"\u003e\u003c/a\u003e\n```\n\n### Workarounds\nIf you're not ignoring attributes then keep processEntities flag true.","status":"published","published":"2026-05-08T16:29:10Z","modified":"2026-05-14T20:37:39Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-91","CWE-611"],"updated_at":"2026-11-02T14:40:09.033429Z"}],"nvd":[{"id":"CVE-2026-44665","description":"fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.","status":"published","published":"2026-05-13T16:16:59.093Z","modified":"2026-10-26T18:10:00.173Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-91"],"updated_at":"2026-11-02T14:12:19.020465Z"}],"osv":[{"id":"CVE-2026-44665","title":"fast-xml-builder: Attribute values with unwanted quotes can bypass malicious or unwanted attributes","description":"fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.","status":"published","published":"2026-05-13T15:24:54.596Z","modified":"2026-10-28T02:30:28.374980199Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-91"],"updated_at":"2026-11-02T15:45:05.172514Z"},{"id":"GHSA-5wm8-gmm8-39j9","title":"fast-xml-builder allows attribute values with unwanted quotes to bypass malicious or unwanted attributes","description":"# Summary\nWhen an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML.\n\n## Detail\n\nMalicious Input\n```\n{\n      a: {\n        \"@_attr\": '\" onClick=\"alert(1)'\n      }\n}\n```\n\nOutput\n```xml\n\u003ca attr=\"\" onClick=\"alert(1)\"\u003e\u003c/a\u003e\n```\n\n### Workarounds\nIf you're not ignoring attributes then keep processEntities flag true.","status":"published","published":"2026-05-08T16:29:10Z","modified":"2026-09-10T03:51:04.681237011Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"},{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-611","CWE-91"],"updated_at":"2026-11-02T15:46:38.911014Z"},{"id":"ROOT-APP-NPM-CVE-2026-44665","title":"CVE-2026-44665 in @rootio/fast-xml-builder - Patched by Root","description":"Root has patched CVE-2026-44665 in the @rootio/fast-xml-builder package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-06-09T13:45:32Z","modified":"2026-06-09T19:30:10.251383684Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:53:27.649662Z"}]}}