CVE intelligence and bounded remediation
CVE-2023-42451 — Mastodon is a free, open-source social network server based on ActivityPub
Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 3.5.14, 4.0.10, 4.1.8, and 4.2.0-rc2, under certain circumstances, attackers can exploit a flaw in domain name normalization to spoof domains they do not own. Versions 3.5.14, 4.0.10, 4.1.8, and 4.2.0-rc2 contain a patch for this issue.
- Severity
- High
- CVSS
- 7.5 (3.1)
- Published
- 2023-09-19
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-706
Affected products
- joinmastodon / mastodon
- joinmastodon / mastodon / 4.2.0
Showing 2 representative product identities from 7 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.
Matched remediation archetype
General vulnerability remediation
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
- Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
- Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.
Remediate safely
- Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
- Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
- Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.