Signal is active with 2 mentions in latest observed window
Recommended action window: Monitor and triage in normal cycle
NVD description
Mastodon is a free, open-source social network server based on ActivityPub. FASP registration requires manual approval by an administrator. In versions 4.4.0 through 4.4.13 and 4.5.0 through 4.5.6, an unauthenticated attacker can register a FASP with an attacker-chosen `base_url` that includes or resolves to a local / internal address, leading to the Mastodon server making requests to that address. This only affects Mastodon servers that have opted in to testing the experimental FASP feature by setting the environment variable `EXPERIMENTAL_FEATURES` to a value including `fasp`. An attacker can force the Mastodon server to make http(s) requests to internal systems. While they cannot control the full URL that is being requested (only the prefix) and cannot see the result of those requests, vulnerabilities or other undesired behavior could be triggered in those systems. The fix is included in the 4.4.14 and 4.5.7 releases. Admins that are actively testing the experimental "fasp" feature should update their systems. Servers not using the experimental feature flag `fasp` are not affected.
Priority
LOW
Exploitation
NONE
PoC
NONE
Patch
AVAILABLE
Momentum
STABLE
If you run products in this scope, you should treat this CVE as relevant to your environment.
| Date | Total | Labels |
|---|
| 2026-02-20 | 1 | Disclosure1 |
| 2026-02-24 | 1 | Disclosure1 |
| 2026-02-25 | 2 | General2 |
Found a couple of bugs in Mastodon. One of them just received CVE-2026-27477. Keeping you safe, one line of code at a time.
Post summary
A new vulnerability (CVE-2026-27477) has been identified in Mastodon, but no further details, exploits, or mitigation steps are provided.
CVE-2026-27477 Mastodon is a free, open-source social network server based on ActivityPub. FASP registration requires manual approval by an administrator. In versions 4.4.0 through … https://www.cve.org/CVERecord?id=CVE-2026-27477
Post summary
The text briefly references CVE‑2026‑27477 for Mastodon, noting a manual approval requirement for FASP registration, but provides no further details or actionable information.
CVE-2026-27477 Server-Side Request Forgery in Mastodon FASP Registration for Experimental Features https://vulmon.com/vulnerabilitydetails?qid=CVE-2026-27477
Post summary
The post references CVE-2026-27477 as a Server‑Side Request Forgery in Mastodon’s FASP registration for experimental features, but provides no further details such as PoC, exploit, or patch information.
Experimental features can introduce unexpected security issues. Take these 2 bugs in Mastodon for example. CVE-2026-27477: https://github.com/mastodon/mastodon/security/advisories/GHSA-46w6-g98f-wxqm CVE-2026-27468: https://github.com/mastodon/mastodon/security/advisories/GHSA-qgmm-vr4c-ggjg
Post summary
The post references two newly disclosed Mastodon CVEs with links to GitHub advisories, but provides no further details on exploitation or mitigation.
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| Part | Vendor | Product | Version | Target SW | Target HW |
|---|---|---|---|---|---|
| App | joinmastodon | mastodon | - | - | - |