CVE-2026-23962

Published: Jan 22, 2026Modified: Jun 17, 2026

7.5

Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitability: 3.9 / Impact: 3.6

Source: security-advisories@github.com (Secondary)

Description

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon versions before v4.3.18, v4.4.12, and v4.5.5 do not have a limit on the maximum number of poll options for remote posts, allowing attackers to create polls with a very large amount of options, greatly increasing resource consumption. Depending on the number of poll options, an attacker can cause disproportionate resource usage in both Mastodon servers and clients, potentially causing Denial of Service either server-side or client-side. Mastodon versions v4.5.5, v4.4.12, v4.3.18 are patched.

Affected (3)

Products: Joinmastodon: Mastodon

1 product

Configuration A

3 vulnerable

Vulnerable Software	Affected Versions
Joinmastodon Mastodon	Before 4.3.18
Joinmastodon Mastodon	From 4.4.0 to 4.4.12
Joinmastodon Mastodon	From 4.5.0 to 4.5.5

Related CWEs

Allocation of Resources Without Limits or Throttling

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.

References (4)

https://github.com/mastodon/mastodon/releases/tag/v4.3.18

Source: security-advisories@github.com

Release Notes

https://github.com/mastodon/mastodon/releases/tag/v4.4.12

Source: security-advisories@github.com

Release Notes

https://github.com/mastodon/mastodon/releases/tag/v4.5.5

Source: security-advisories@github.com

Release Notes

https://github.com/mastodon/mastodon/security/advisories/GHSA-gg8q-rcg7-p79g

Source: security-advisories@github.com

Vendor Advisory

Timeline

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