Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 3.5.0 and prior to versions 3.5.9, 4.0.5, and 4.1.3, attackers using carefully crafted media files can cause Mastodon's media processing code to create arbitrary files at any location. This allows attackers to create and overwrite any file Mastodon has access to, allowing Denial of Service and arbitrary Remote Code Execution. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
| Link | Tags |
|---|---|
| https://github.com/mastodon/mastodon/security/advisories/GHSA-9928-3cp5-93fm | third party advisory |
| https://github.com/mastodon/mastodon/commit/dc8f1fbd976ae544720a4e07120d9a91b2722440 | third party advisory patch |
| https://github.com/mastodon/mastodon/releases/tag/v3.5.9 | third party advisory |
| https://github.com/mastodon/mastodon/releases/tag/v4.0.5 | third party advisory |
| https://github.com/mastodon/mastodon/releases/tag/v4.1.3 | third party advisory |
| http://www.openwall.com/lists/oss-security/2023/07/06/4 | mailing list |