CVE-2025-27157

Mastodon is a self-hosted, federated microblogging platform. Starting in version 4.2.0 and prior to versions 4.2.16 and 4.3.4, the rate limits are missing on `/auth/setup`. Without those rate limits, an attacker can craft requests that will send an email to an arbitrary addresses. Versions 4.2.16 and 4.3.4 fix the issue.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/mastodon/mastodon/commit/06f879ce9bea195344ac9f71e6799eea500628ec	Patch
https://github.com/mastodon/mastodon/security/advisories/GHSA-v39f-c9jj-8w7h	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:joinmastodon:mastodon::::::::
	cpe:2.3:a:joinmastodon:mastodon::::::::

History

24 Jun 2025, 15:59

Type	Values Removed	Values Added
References	~~() https://github.com/mastodon/mastodon/commit/06f879ce9bea195344ac9f71e6799eea500628ec -~~	() https://github.com/mastodon/mastodon/commit/06f879ce9bea195344ac9f71e6799eea500628ec - Patch
References	~~() https://github.com/mastodon/mastodon/security/advisories/GHSA-v39f-c9jj-8w7h -~~	() https://github.com/mastodon/mastodon/security/advisories/GHSA-v39f-c9jj-8w7h - Vendor Advisory
Summary		(es) Mastodon es una plataforma de microblogging federada y alojada por el usuario. A partir de la versión 4.2.0 y antes de las versiones 4.2.16 y 4.3.4, faltan los límites de velocidad en `/auth/setup`. Sin esos límites de velocidad, un atacante puede crear solicitudes que envíen un correo electrónico a direcciones arbitrarias. Las versiones 4.2.16 y 4.3.4 solucionan el problema.
First Time		Joinmastodon mastodon Joinmastodon
CPE		cpe:2.3:a:joinmastodon:mastodon::::::::

27 Feb 2025, 17:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-02-27 17:15

Updated : 2025-06-24 15:59

NVD link : CVE-2025-27157

Mitre link : CVE-2025-27157

CVE.ORG link : CVE-2025-27157

JSON object : View

Products Affected

joinmastodon

mastodon

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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