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TI-2026-41426 Aliases CVE-2026-57575

Misskey: SSRF bypass in URL Preview

Priority LOW 37CWE-918Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Misskey is an open source, federated social media platform. Prior to 2026.6.0, Misskey contains a Server-Side Request Forgery (SSRF) vulnerability in URL preview functionality in UrlPreviewService. Due to missing network restrictions before establishing outbound connections, a remote attacker can cause the Misskey server to initiate HTTP requests to loopback, private, or link-local services. Because IP address validation takes place after the request has been sent and the process is subsequently rejected, no sensitive internal data is believed to be transmitted back or exposed to the attacker. This issue is fixed in version 2026.6.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00604 49th percentileScored 2026-11-07
Fix Fixed misskey (misskey-dev): 2026.6.0

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-devmisskeybefore 2026.6.02026.6.0Patch availableCNA
  • misskey Vendormisskey-dev Affected before 2026.6.0 Fixed in 2026.6.0 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

  • Fix · CNA misskey (misskey-dev) Fixed in 2026.6.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-57575

References

Other 3

  • 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