{"id":"CVE-2021-26539","aliases":["CLSA-2026-1776644763","EUVD-2021-1183","GHSA-rjqq-98f6-6j3r","ROOT-APP-NPM-CVE-2021-26539"],"status":"published","title":"Improper Input Validation in sanitize-html","description":"Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the \"allowedIframeHostnames\" option.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.01977,"percentile":0.80678,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20"],"published":"2021-02-08T16:16:06Z","modified":"2026-10-24T10:47:54Z","fixes":[{"ecosystem":"npm","package":"sanitize-html","fixed_in":["2.3.1"],"sources":["ghsa","osv"]},{"ecosystem":"Root:npm","package":"@rootio/sanitize-html","fixed_in":["1.4.2-root.io.7","1.4.2-root.io.8","1.4.2-root.io.9"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"sanitize-html","fixed_in":["1.4.2-aikido.9"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"sanitize-html","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.3.1"}]}]},{"source":"osv","ecosystem":"TuxCare:npm","package":"sanitize-html","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.27.5-tuxcare.0"},{"fixed":"1.27.5-tuxcare.2"}]}],"versions":["1.27.5","1.27.5-tuxcare.1"],"bundled":3},{"source":"osv","ecosystem":"npm","package":"sanitize-html","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.3.1"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"@rootio/sanitize-html","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2-root.io.7"},{"fixed":"1.4.2-root.io.8"},{"fixed":"1.4.2-root.io.9"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"sanitize-html","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2-aikido.9"}]}]}],"products":[{"vendor":"apostrophecms","product":"sanitize-html"}],"references":[{"url":"https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#231-2021-01-22","tags":["x_refsource_MISC","x_transferred","Release Notes","Third Party Advisory","advisory","web"]},{"url":"https://github.com/apostrophecms/sanitize-html/pull/458","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://advisory.checkmarx.net/advisory/CX-2021-4308","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","evidence","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-26539","tags":["advisory"]},{"url":"https://github.com/apostrophecms/sanitize-html/commit/bdf7836ef8f0e5b21f9a1aab0623ae8fcd09c1da","tags":["web"]},{"url":"https://github.com/advisories/GHSA-rjqq-98f6-6j3r"},{"url":"https://github.com/apostrophecms/sanitize-html","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2021-26539","description":"Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the \"allowedIframeHostnames\" option.","status":"published","published":"2021-02-08T16:16:06Z","modified":"2024-08-03T20:26:25.401Z","updated_at":"2026-11-02T14:32:57.033395Z"}],"euvd":[{"id":"EUVD-2021-1183","description":"Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the \"allowedIframeHostnames\" option.","status":"published","published":"2021-02-08T16:16:06Z","modified":"2024-08-03T20:26:25Z","updated_at":"2026-11-03T03:24:51.962182Z"}],"ghsa":[{"id":"GHSA-rjqq-98f6-6j3r","title":"Improper Input Validation in sanitize-html","description":"Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the \"allowedIframeHostnames\" option.","status":"published","published":"2021-05-06T16:10:05Z","modified":"2023-04-21T19:19:09Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:36:51.39133Z"}],"nvd":[{"id":"CVE-2021-26539","description":"Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the \"allowedIframeHostnames\" option.","status":"published","published":"2021-02-08T17:15:13.673Z","modified":"2026-06-17T03:43:27.283Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"updated_at":"2026-11-02T14:06:49.660551Z"}],"osv":[{"id":"CVE-2021-26539","description":"Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the \"allowedIframeHostnames\" option.","status":"published","published":"2021-02-08T17:15:13.673Z","modified":"2026-10-24T10:47:54.254670608Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:18.778776Z"},{"id":"GHSA-rjqq-98f6-6j3r","title":"Improper Input Validation in sanitize-html","description":"Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the \"allowedIframeHostnames\" option.","status":"published","published":"2021-05-06T16:10:05Z","modified":"2023-11-08T04:05:21.094678Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T15:46:55.877614Z"},{"id":"CLSA-2026-1776644763","title":"TuxCare security update for sanitize-html (3 CVEs)","description":"TuxCare rebuilt sanitize-html to address 3 CVEs. Fixed in 1.27.5-tuxcare.2.","status":"published","published":"2026-08-04T14:52:18Z","modified":"2026-10-15T09:47:07.395053353Z","updated_at":"2026-11-02T15:43:44.009773Z"},{"id":"ROOT-APP-NPM-CVE-2021-26539","title":"CVE-2021-26539 in @rootio/sanitize-html - Patched by Root","description":"Root has patched CVE-2021-26539 in the @rootio/sanitize-html package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-06-04T20:57:52Z","modified":"2026-06-05T01:30:45.290906896Z","updated_at":"2026-11-02T15:53:27.362922Z"}]}}