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TI-2024-25219 Aliases CVE-2024-37903

Mastodon has improper authorship check on audience extension for existing posts

Priority MEDIUM 42CWE-862Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-862.

Summary

Mastodon is a self-hosted, federated microblogging platform. Starting in version 2.6.0 and prior to versions 4.1.18 and 4.2.10, by crafting specific activities, an attacker can extend the audience of a post they do not own to other Mastodon users on a target server, thus gaining access to the contents of a post not intended for them. Versions 4.1.18 and 4.2.10 contain a patch for this issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0053 45th percentileScored 2026-11-07
Fix Fixed mastodon (mastodon): 4.1.18, 4.2.10

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
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
mastodonmastodon2.6.0 to before 4.1.18; 4.2.0 to before 4.2.104.1.18, 4.2.10Patch availableCNA
  • mastodon Vendormastodon Affected 2.6.0 to before 4.1.18; 4.2.0 to before 4.2.10 Fixed in 4.1.18, 4.2.10 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*2.6.0 to before 4.1.18; 4.2.0 to before 4.2.10Vulnerablemastodon
  • cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:* Versions 2.6.0 to before 4.1.18; 4.2.0 to before 4.2.10 Vulnerable ·mastodon

Remediation

  • Fix · CNA mastodon (mastodon) Fixed in 4.1.18, 4.2.10

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-37903

References

Patch 2

Advisory 1

Other 2

  • 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