{"id":"CVE-2026-104021","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-104021","generatedAt":"2026-10-28T02:12:49.776Z","title":"The Fastcache by Host.it plugin for WordPress is vulnerable to Code Injection in all versions up to, and including, 1.7.4 via the `fastcache_settings[cache_cookie_exclude][]` parameter.","description":"The Fastcache by Host.it plugin for WordPress is vulnerable to Code Injection in all versions up to, and including, 1.7.4 via the `fastcache_settings[cache_cookie_exclude][]` parameter. This is due to the plugin registering the `cache_cookie_exclude` setting via `register_setting()` without a `sanitize_callback`, while `buildSiteHtaccessRules()` applies only `trim()` to each cookie value before interpolating it directly into an Apache `RewriteCond` line — a normalization that strips surrounding whitespace but leaves embedded newlines intact, allowing an attacker to break out of the capture group and append arbitrary directives. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary Apache directives into the site's `.htaccess` file via `file_put_contents()`, enabling server-level configuration changes such as setting `php_value auto_prepend_file` to execute attacker-controlled PHP code on every request.","published":"2026-10-10T05:16:40.000Z","lastModified":"2026-10-13T13:30:22.000Z","status":"Deferred","sourceIdentifier":"security@wordfence.com","cvss":{"version":"3.1","score":7.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-94"],"affected":[],"epss":{"score":0.00388,"percentile":0.32661,"date":"2026-10-26","history":[{"date":"2026-10-10","score":0.004,"percentile":0.32166}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-10T05:16:40.000Z","detail":{"score":"7.2","severity":"HIGH","publishedAt":"2026-10-10T05:16:39.503Z"},"summary":"New CVE, high severity (CVSS 7.2)."}],"references":[{"url":"https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Admin.php#L73","source":"security@wordfence.com"},{"url":"https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Core/Platform/Utility.php#L420","source":"security@wordfence.com"},{"url":"https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Core/Platform/Utility.php#L521","source":"security@wordfence.com"},{"url":"https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Core/Platform/Utility.php#L545","source":"security@wordfence.com"},{"url":"https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Dispatcher.php#L480","source":"security@wordfence.com"},{"url":"https://plugins.trac.wordpress.org/changeset?reponame=&old=3735944%40fastcache-by-host-it&new=3735944%40fastcache-by-host-it","source":"security@wordfence.com"},{"url":"https://www.wordfence.com/threat-intel/vulnerabilities/id/d72d7a21-0bea-4a32-b92b-326f47998b80?source=cve","source":"security@wordfence.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-104021","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}