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Redirect Filter Bypass

Low
syuilo published GHSA-7899-w6c4-vqc4 May 5, 2025

Package

npm @misskey-dev/summaly (npm)

Affected versions

>=3.0.1

Patched versions

5.2.1

Description

Summary

A logic error in the main summaly function causes the allowRedirects option to never be passed to any plugins, and as a result, isn't enforced.

Details

In the main summaly function, a new scrapingOptions object is created and passed to either the matched plugin, if any, or the default summarize function. The issue here is that the new scrapingOptions object is not provided the allowRedirects property of opts.

PoC

  • Publish a post containing a link to any URL that redirects on Misskey.
  • A preview will be generated for the target of the redirect, despite Misskey passing allowRedirects: false.

Impact

Misskey will follow redirects, despite explicitly requesting not to.

Severity

Low

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
None

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:N

CVE ID

CVE-2025-46553

Weaknesses

Improper Control of a Resource Through its Lifetime

The product does not maintain or incorrectly maintains control over a resource throughout its lifetime of creation, use, and release. Learn more on MITRE.

Credits