CVE-2025-46340

May 5, 2025, 8:54 p.m.

7.2
High

Description

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.

Product(s) Impacted

Vendor Product Versions
Misskey
  • Misskey
  • 12.0.0-2025.4.1

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-20
Improper Input Validation
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a misskey misskey 12.0.0-2025.4.1 / / / / / / /

CVSS Score

7.2 / 10

CVSS Data - 3.1

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Privileges Required: NONE
  • Scope: CHANGED
  • Confidentiality Impact: LOW
  • Integrity Impact: LOW
  • Availability Impact: NONE
  • CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

    View Vector String

Timeline

Published: May 5, 2025, 7:15 p.m.
Last Modified: May 5, 2025, 8:54 p.m.

Status : Awaiting Analysis

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

security-advisories@github.com

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.