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CVE-2026-46713 (GCVE-0-2026-46713)

Vulnerability from cvelistv5 – Published: 2026-08-03 21:37 – Updated: 2026-08-04 15:44
VLAI
Title
Misskey: JSON-LD signature validation + compaction may lead to improper activity handling
Summary
Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.
Severity
9.2 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-04 15:44 UTC
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
References
Impacted products
Vendor Product Version CPE status
misskey-dev misskey Affected: >= 12.37.0, < 2026.5.4
guessed Create a notification for this product.
Show details on NVD website
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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