CVE-2024-52591Network attack vector

User impersonation via missing same-origin validation

Published Dec 18, 2024 · Updated Dec 19, 2024

Improper input validation in Misskey before 2024.11.0-alpha.3 allows remote attackers to impersonate users via forged ActivityPub objects. ApRequestService.signedGet and HttpRequestService.getActivityJson fail to enforce same-origin relationships between fetched URLs and object identifiers. No account or user interaction is required; a receiving instance accepts the spoofed profile or note as valid and leaves the attacker in control.

CVSS severity8.8
High
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Misskey before 2024.11.0-alpha.3 allows remote attackers to impersonate users via forged ActivityPub objects. ApRequestService.signedGet and HttpRequestService.getActivityJson fail to enforce same-origin relationships between fetched URLs and object identifiers. No account or user interaction is required; a receiving instance accepts the spoofed profile or note as valid and leaves the attacker in control.

The record

CVE
CVE-2024-52591
Published
Dec 18, 2024
Updated
Dec 19, 2024
Vendor
Misskey Project
Product
Misskey
Classifications
CWE-20, T1656.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 18, 2024CVE publishedPublication date reported by the CVE source.
  2. Dec 19, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2024.11.0-alpha.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Misskey Project · Misskeyversion=< 2024.11.0-alpha.3

Published CVSS scores

8.8GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:L/SI:N/SA:L
9.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1656.001Social Media Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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