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TI-2026-73348 Aliases CVE-2026-104816

Cross-site scripting in Misskey RSS feed item links

Priority MEDIUM 44CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Active
Attack complexity
Low
Attack requirements
None
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

Misskey from 12.0.0 before 2026.7.0 displays RSS feed item links without verifying their URL schemes (CWE-79). An attacker who controls feed content can supply a link with an unsafe scheme that runs script when a user clicks it in an RSS widget. The attack requires user interaction but no privileges.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Misskey is an open source, federated social media platform. From 12.0.0 until 2026.7.0, the RSS components display feed item links from configured feeds without verifying their URL schemes. Missing URL scheme verification allows an attacker who controls feed content to provide an unsafe-scheme link that causes script execution when a user clicks it in an RSS widget. This issue is fixed in version 2026.7.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0063 50th percentileScored 2026-11-07
Fix Fixed misskey (misskey-dev): 2026.7.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
misskey-devmisskey12.0.0 – 13.14.2; 2023.9.0-beta.1 to before 2026.7.02026.7.0Patch availableCNA
  • misskey Vendormisskey-dev Affected 12.0.0 – 13.14.2; 2023.9.0-beta.1 to before 2026.7.0 Fixed in 2026.7.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:misskey:misskey:*:*:*:*:*:*:*:*——misskey-dev
  • cpe:2.3:a:misskey:misskey:*:*:*:*:*:*:*:* Versions — — ·misskey-dev

Remediation

Upgrade Misskey to version 2026.7.0, which fixes this issue.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA misskey (misskey-dev) Fixed in 2026.7.0

Timeline

  1. 2026-10-13 Threatist record created from CVE-2026-104816
  2. 2026-10-28 EPSS moved to the 50th–90th percentile

References

Other 4

  • TI-2025-18599 Misskey CSRF vulnerability due to insecure configuration of authentication cookie attributes CVSS 3.1HIGH 8.2
  • TI-2025-29081 Misskey CSS Style Injection Vulnerability In `MkUrlPreview` CVSS 3.1HIGH 7.2
  • TI-2025-40906 Misskey has a login rate limit bypass via spoofed X-Forwarded-For header CVSS 4.0MEDIUM 6.9
  • TI-2025-29276 Misskey Directory Traversal Vulnerability in AiScript via `Mk:api` CVSS 3.1HIGH 7.5
  • TI-2025-40839 misskey.js's export data contains private post data CVSS 4.0HIGH 7.1
  • TI-2025-29271 @misskey-dev/summaly Redirect Filter Bypass CVSS 4.0LOW 2.1
See all 38 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences