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TI-2025-38494 Aliases CVE-2025-62176

Mastadon streaming server allows OAuth clients without the `read` scope to subscribe to public channels

Priority LOW 20CWE-280Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Mastodon is a free, open-source social network server based on ActivityPub. In Mastodon before 4.4.6, 4.3.14, and 4.2.27, the streaming server accepts serving events for public timelines to clients using any valid authentication token, even if those tokens lack the read:statuses scope. This allows OAuth clients without the read scope to subscribe to public channels and receive public timeline events. The impact is limited, as this only affects new public posts published on the public timelines and requires an otherwise valid token, but this may lead to unexpected access to public posts in a limited-federation setting. This issue has been patched in versions 4.4.6, 4.3.14, and 4.2.27. No known workarounds exist.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00275 20th percentileScored 2026-11-07
Fix Fixed mastodon (mastodon): 4.4.6, 4.3.14, 4.2.27

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
mastodonmastodon4.4.0-beta.1 to before 4.4.6; 4.3.0-beta.1 to before 4.3.14; before 4.2.274.4.6, 4.3.14, 4.2.27Patch availableCNA
  • mastodon Vendormastodon Affected 4.4.0-beta.1 to before 4.4.6; 4.3.0-beta.1 to before 4.3.14; before 4.2.27 Fixed in 4.4.6, 4.3.14, 4.2.27 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*before 4.2.27; 4.3.0 to before 4.3.14; 4.4.0 to before 4.4.6Vulnerablemastodon
  • cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:* Versions before 4.2.27; 4.3.0 to before 4.3.14; 4.4.0 to before 4.4.6 Vulnerable ·mastodon

Remediation

  • Fix · CNA mastodon (mastodon) Fixed in 4.4.6, 4.3.14, 4.2.27

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-62176

References

Patch 1

Advisory 1

  • TI-2022-02004 Improper Restriction of Excessive Authentication Attempts in mastodon/mastodon CVSS 3.1CRITICAL 9.8
  • TI-2025-34613 Mastodon e‑mail throttle misconfiguration allows unlimited email confirmations against unconfirmed emails CVSS 3.1HIGH 7.5
  • TI-2022-22936 Mastodon through 4.0.2 allows attackers to cause a denial of service (large Sidekiq pull… CVSS 3.1HIGH 7.5
  • TI-2023-18301 Mastodon vulnerable to arbitrary file creation through media attachments CVSS 3.1CRITICAL 10.0
  • TI-2023-13359 Mastodon's blind LDAP injection in login allows the attacker to leak arbitrary attributes from LDAP database CVSS 3.1HIGH 7.7
  • TI-2024-16846 External OpenID Connect Account Takeover by E-Mail Change in mastodon CVSS 3.1HIGH 7.4
See all 41 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences