CVE-2024-23832Network attack vector

Remote account takeover via trusted self-reported identifiers

Published Feb 1, 2024 · Updated Feb 13, 2025

Origin validation error in Mastodon's ActivityPub ingestion allows remote attackers to impersonate remote accounts via crafted objects. FetchRemoteResource passes a fetched object's self-reported id instead of its queried URL, causing ingestion to trust attacker-controlled origin data. No authentication or user interaction is required, and spoofed actors can overwrite objects and intercept subsequent federated traffic.

CVSS severity9.4
Critical
EPSS probability2.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Origin validation error in Mastodon's ActivityPub ingestion allows remote attackers to impersonate remote accounts via crafted objects. FetchRemoteResource passes a fetched object's self-reported id instead of its queried URL, causing ingestion to trust attacker-controlled origin data. No authentication or user interaction is required, and spoofed actors can overwrite objects and intercept subsequent federated traffic.

The record

CVE
CVE-2024-23832
Published
Feb 1, 2024
Updated
Feb 13, 2025
Vendor
Mastodon
Product
Mastodon
Classifications
CWE-346, T1656
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 1, 2024CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=< 3.5.17
  2. Affected versionversion=>= 4.0.0, < 4.0.13
  3. Affected versionversion=>= 4.1.0, < 4.1.13
  4. Affected versionversion=>= 4.2.0, < 4.2.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mastodon · Mastodonversion=< 3.5.17; version=>= 4.0.0, < 4.0.13; version=>= 4.1.0, < 4.1.13; version=>= 4.2.0, < 4.2.5

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.4GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

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-346Origin Validation Error
T1656Impersonation

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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