CVE Explorer
CVE-2026-33868
Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.5.8, 4.4.15, and 4.3.21, an unauthenticated Open Redirect vulnerability (CWE-601) exists in the `/web/*` route due to improper handling of URL-encoded path segments. An attacker can craft a specially encoded URL that causes the application to redirect users to an arbitrary external domain, enabling phishing attacks and potential OAuth credential theft. The issue occurs because URL-encoded slashes (`%2
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"product":"mastodon","vendor":"mastodon","versions":[{"status":"affected","version":">= 4.5.0, < 4.5.8"},{"status":"affected","version":">= 4.4.0, < 4.4.15"},{"status":"affected","version":"< 4.3.21"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:2857d772844940445a842a37788e0bf654bcb1e6c0cd559b8973a6132428d61c · sha256:ff39dba63987d223… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","version":"3.1"},"metric_type":"cvssV3_1"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:2857d772844940445a842a37788e0bf654bcb1e6c0cd559b8973a6132428d61c · sha256:ff39dba63987d223… · /containers/cna/metrics/0/cvssV3_1
CWE assertions
1 source assertion{"cweId":"CWE-601","description":"CWE-601: URL Redirection to Untrusted Site ('Open Redirect')","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:2857d772844940445a842a37788e0bf654bcb1e6c0cd559b8973a6132428d61c · sha256:ff39dba63987d223… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"name":"https://github.com/mastodon/mastodon/security/advisories/GHSA-xqw8-4j56-5hj6","tags":["x_refsource_CONFIRM"],"url":"https://github.com/mastodon/mastodon/security/advisories/GHSA-xqw8-4j56-5hj6"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:2857d772844940445a842a37788e0bf654bcb1e6c0cd559b8973a6132428d61c · sha256:ff39dba63987d223… · /containers/cna/references/0
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.