CVE-2026-41887

Sažetak

Flarum is open-source forum software. Prior to versions 1.8.16 and 2.0.0-rc.1, Flarum's patch for CVE-2023-27577 restricted the @import and data-uri() LESS features in the custom_less setting, but the same restriction was never applied to other settings registered as LESS config variables (for example theme_primary_color and theme_secondary_color, as well as any key registered via Extend\Settings::registerLessConfigVar()). Those values are interpolated verbatim into the LESS source at compile time, allowing an authenticated administrator to craft a theme-color value that injects an arbitrary @import directive into the compiled forum.css. Because the underlying LESS parser honours @import (inline) '<path>', an attacker can read arbitrary files reachable by the PHP process (local file inclusion) or trigger outbound HTTP(S) requests (server-side request forgery). This issue has been patched in versions 1.8.16 and 2.0.0-rc.1.

Reference

CVSS

Base:	4.9
Impact:	3.6
Exploitability:	1.2

Pristup

Vektor	Složenost	Autentikacija
NETWORK	LOW	HIGH

Impact

Povjerljivost	Cjelovitost	Dostupnost
HIGH	NONE	NONE

CVSS vektor

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

Zadnje važnije ažuriranje

08-05-2026 - 20:16

Objavljeno

08-05-2026 - 17:16