Vulnerability in Joinmastodon Mastodon
CVE-2026-22246
Mastodon is a free, open-source social network server based on ActivityPub. Mastodon 4.3 added notifications of severed relationships, allowing end-users to inspect the relationships they lost as the result of a moderation action. The code…
EPSS: 0.002 (13.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Joinmastodon Mastodon
- Mastodon — versions < 4.3.17, >= 4.4.0-beta.1, < 4.4.11, >= 4.5.0-beta.1, < 4.5.4
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-22246?
- CVE-2026-22246 is a medium-severity vulnerability in Joinmastodon Mastodon, classified under Insertion of Sensitive Information into Sent Data. CVSS score: 6.5/10. Published 2026-01-08.
- How severe is CVE-2026-22246?
- Medium severity. CVSS v3 base score is 6.5 out of 10.