CVE-2026-104021 (GCVE-0-2026-104021)
Vulnerability from cvelistv5
Published
2026-10-10 04:26
Modified
2026-10-11 16:55
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-94 - Improper Control of Generation of Code ('Code Injection')
Summary
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| hostspa | Fastcache by Host.it |
Version: 0 ≤ 1.7.4 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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