CVE-2026-50129

High

Description

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.11, 4.4.18, and 4.3.24, a DoS can be triggered by (Uncaught Exception vulerability), due to missing exception handling in the math sanitizer. Malformed <math> nodes can result in a DoS of a whole server or targeted users services, depending on the type of action that includes the malformed nodes and the services interacting with it. This vulnerability is fixed in 4.5.11, 4.4.18, and 4.3.24.

SeverityHigh
CVSS7.5
Exploit probability—
ProductMastodon
PublishedJun 24, 2026
First seenJun 24, 2026
Weakness typeCWE-248CWE-248

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
mastodon mastodon>= 4.5.0-beta.1, < 4.5.11, >= 4.4.0-beta.1, < 4.4.18, < 4.3.24—

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