--- cve: "CVE-2024-25623" severity: "HIGH" cvss: 8.5 epss: "52%" vendor: "mastodon" kev: false exploited: false published: "2024-02-19 16:15:51" tags: [cve, security, high] source: tsecurity.de CVE-Dossier exported: "2026-09-17T23:11:07+02:00" --- # CVE-2024-25623 > 8.5 HIGH · 🧪 PoC ## Beschreibung Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.2.7, 4.1.15, 4.0.15, and 3.5.19, when fetching remote statuses, Mastodon doesn't check that the response from the remote server has a `Content-Type` header value of the Activity Streams media type, which allows a threat actor to upload a crafted Activity Streams document to a remote server and make a Mastodon server fetch it, if the remote server accepts arbitrary user uploads. The vulnerability allows a threat actor to impersonate an account on a remote server that satisfies all of the following properties: allows the attacker to register an account; accepts arbitrary user-uploaded documents and places them on the same domain as the ActivityPub actors; and serves user-uploaded document in response to requests with an `Accept` header value of the Activity Streams media type. Versions 4.2.7, 4.1.15, 4.0.15, and 3.5.19 contain a fix for this issue. ## CVSS-Vektor ``` CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N ``` | Metrik | Wert | Bewertung | |---|---|---| | AV Angriffsvektor | Netzwerk | bad | | AC Komplexität | Gering | bad | | PR Privilegien | Gering | warn | | UI Interaktion | Keine | bad | | S Scope | Verändert | bad | | C Vertraulichkeit | Gering | warn | | I Integrität | Hoch | bad | | A Verfügbarkeit | Keine | good | ## Patch verfügbar (OSV) - e9123ad691727ffec3672ff3912ef56e67c930ef (Commit) - e5726d211fd3dc1d640f202e808e25891d765586 (Commit) ## Referenzen - - --- _Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2024-25623) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_