CVE-2024-25618Public exploitNetwork attack vector

Account takeover via email-only SSO identity reattachment

Published Feb 14, 2024 · Updated May 12, 2025

Improper authentication in Mastodon before 3.5.18 and select 4.x releases allows remote attackers to take over accounts through external SSO. The find_for_oauth path reattaches a first-seen provider identity to an existing local user by matching only the provider-supplied email address. Exploitation requires a configured CAS, SAML, or OIDC provider that permits mutable or conflicting email claims, and it grants control of the matched local account.

CVSS severity4.2
Medium
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Mastodon before 3.5.18 and select 4.x releases allows remote attackers to take over accounts through external SSO. The find_for_oauth path reattaches a first-seen provider identity to an existing local user by matching only the provider-supplied email address. Exploitation requires a configured CAS, SAML, or OIDC provider that permits mutable or conflicting email claims, and it grants control of the matched local account.

The record

CVE
CVE-2024-25618
Published
Feb 14, 2024
Updated
May 12, 2025
Vendor
Mastodon
Product
Mastodon
Classifications
CWE-287, CWE-306, T1078
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 14, 2024CVE publishedPublication date reported by the CVE source.
  2. May 12, 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=< 3.5.18
  2. Affected versionversion=>= 4.0.0, < 4.0.14
  3. Affected versionversion=>= 4.1.0, < 4.1.14
  4. Affected versionversion=>= 4.2.0, < 4.2.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mastodon · Mastodonversion=< 3.5.18; version=>= 4.0.0, < 4.0.14; version=>= 4.1.0, < 4.1.14; version=>= 4.2.0, < 4.2.6

Published CVSS scores

7.4NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
4.2GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-306Missing Authentication for Critical Function
T1078Valid Accounts

Public exploit references

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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