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TI-2023-22617 Aliases CVE-2023-42452

Mastodon vulnerable to Stored XSS through the translation feature

Priority LOW 28CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

Mastodon is a free, open-source social network server based on ActivityPub. In versions on the 4.x branch prior to versions 4.0.10, 4.2.8, and 4.2.0-rc2, under certain conditions, attackers can abuse the translation feature to bypass the server-side HTML sanitization, allowing unescaped HTML to execute in the browser. The impact is limited thanks to Mastodon's strict Content Security Policy, blocking inline scripts, etc. However a CSP bypass or loophole could be exploited to execute malicious XSS. Furthermore, it requires user interaction, as this can only occur upon clicking the “Translate” button on a malicious post. Versions 4.0.10, 4.2.8, and 4.2.0-rc2 contain a patch for this issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00438 38th percentileScored 2026-11-07
Fix Fixed mastodon (mastodon): 4.0.10, 4.1.8, 4.2.0-rc2

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
mastodonmastodon4.0.0 to before 4.0.10; 4.1.0 to before 4.1.8; 4.2.0-beta1 to before 4.2.0-rc24.0.10, 4.1.8, 4.2.0-rc2Patch availableCNA
  • mastodon Vendormastodon Affected 4.0.0 to before 4.0.10; 4.1.0 to before 4.1.8; 4.2.0-beta1 to before 4.2.0-rc2 Fixed in 4.0.10, 4.1.8, 4.2.0-rc2 Patch available CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*4.0.0 to before 4.0.10; 4.1.0 to before 4.1.8Vulnerablemastodon
cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta1:*:*:*:*:*:*4.2.0 beta1Vulnerablemastodon
cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta2:*:*:*:*:*:*4.2.0 beta2Vulnerablemastodon
cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta3:*:*:*:*:*:*4.2.0 beta3Vulnerablemastodon
cpe:2.3:a:joinmastodon:mastodon:4.2.0:rc1:*:*:*:*:*:*4.2.0 rc1Vulnerablemastodon
  • cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:* Versions 4.0.0 to before 4.0.10; 4.1.0 to before 4.1.8 Vulnerable ·mastodon
  • cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta1:*:*:*:*:*:* Versions 4.2.0 beta1 Vulnerable ·mastodon
  • cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta2:*:*:*:*:*:* Versions 4.2.0 beta2 Vulnerable ·mastodon
  • cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta3:*:*:*:*:*:* Versions 4.2.0 beta3 Vulnerable ·mastodon
  • cpe:2.3:a:joinmastodon:mastodon:4.2.0:rc1:*:*:*:*:*:* Versions 4.2.0 rc1 Vulnerable ·mastodon

Remediation

  • Fix · CNA mastodon (mastodon) Fixed in 4.0.10, 4.1.8, 4.2.0-rc2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-42452

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