CVE-2025-46340

Sažetak

Misskey is an open source, federated social media platform. Starting in version 12.0.0 and prior to version 2025.4.1, due to an oversight in the validation performed in `UrlPreviewService` and `MkUrlPreview`, it is possible for an attacker to inject arbitrary CSS into the `MkUrlPreview` component. `UrlPreviewService.wrap` falls back to returning the original URL if it's using a protocol that is likely to not be understood by Misskey, IE something other than `http` or `https`. This both can de-anonymize users and_allow further attacks in the client. Additionally, `MkUrlPreview` doesn't escape CSS when applying a `background-image` property, allowing an attacker to craft a URL that applies arbitrary styles to the preview element. Theoretically, an attacker can craft a CSS injection payload to create a fake error message that can deceive the user into giving away their credentials or similar sensitive information. Version 2025.4.1 contains a patch for the issue.

Reference

CVSS

Base:	7.2
Impact:	2.7
Exploitability:	3.9

Pristup

Vektor	Složenost	Autentikacija
NETWORK	LOW	NONE

Impact

Povjerljivost	Cjelovitost	Dostupnost
LOW	LOW	NONE

CVSS vektor

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

Zadnje važnije ažuriranje

05-05-2025 - 20:54

Objavljeno

05-05-2025 - 19:15