Description
Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.3.19, 4.4.13, 4.5.6, Mastodon is vulnerable to web cache poisoning via `Rails.cache. When AUTHORIZED_FETCH is enabled, the ActivityPub endpoints for pinned posts and featured hashtags have contents that depend on the account that signed the HTTP request. However, these contents are stored in an internal cache and reused with no regards to the signing actor. As a result, an empty response generated for a blocked user account may be served to requests from legitimate non-blocked actors, or conversely, content intended for non-blocked actors may be returned to blocked actors. This issue has been patched in versions 4.3.19, 4.4.13, 4.5.6.
INFO
Published Date :
2026-02-04T21:42:09.460Z
Last Modified :
2026-02-05T18:30:11.981Z
Source :
GitHub_M
AFFECTED PRODUCTS
The following products are affected by CVE-2026-25540 vulnerability.
| Vendors | Products |
|---|---|
| Joinmastodon |
|
REFERENCES
Here, you will find a curated list of external links that provide in-depth information to CVE-2026-25540.