CVE-2026-41259

7.5 HIGH
Published: April 23, 2026 Modified: April 28, 2026
View on NVD

Description

Mastodon is a free, open-source social network server based on ActivityPub. Prior to v4.5.9, v4.4.16, and v4.3.22, Mastodon allows restricting new user sign-up based on e-mail domain names, and performs basic validation on e-mail addresses, but fails to restrict characters that are interpreted differently by some mailing servers. This vulnerability is fixed in v4.5.9, v4.4.16, and v4.3.22.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/mastodon/mastodon/security/advisories/GHSA-5r37-qpwq-2jhh
Source: security-advisories@github.com
Vendor Advisory

1 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
0.0%
12th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

joinmastodon