CVE-2025-27157

low-risk
Published 2025-02-27

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.

Do I need to act?

-
0.24% chance of exploitation
EPSS score — low exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.3/10 Medium
NETWORK / LOW complexity

Affected Products (1)

Affected Vendors

Joinmastodon

References (2)

Patch https://github.com/mastodon/mastodon/commit/06f879ce9bea195344ac9f71e6799eea5006...
Vendor Advisory https://github.com/mastodon/mastodon/security/advisories/GHSA-v39f-c9jj-8w7h
27
/ 100
low-risk
Severity 21/34 · High
Exploitability 1/34 · Minimal
Exposure 5/34 · Minimal