High-Severity Vulnerability in Mastodon Allows Remote Security Bypass
Summary
The Italian National Cybersecurity Agency (ACN) issued alert AL04/260424/CSIRT-ITA on 24 April 2026 disclosing a high-severity security vulnerability (CVE-2026-41259) in Mastodon, an open-source social network server. The vulnerability, classified as Security Feature Bypass, allows a remote attacker to circumvent security controls on affected systems. Affected versions include Mastodon 4.3.x prior to 4.3.22, 4.4.x prior to 4.4.16, and 4.5.x prior to 4.5.9. ACN rates the system impact as medium (63.46) and recommends updating vulnerable installations to patched versions as specified in the vendor security bulletin.
“Tale vulnerabilità, qualora sfruttata, potrebbe permettere a un utente malintenzionato remoto di eludere le funzionalità di sicurezza sui sistemi interessati.”
About this source
GovPing monitors Italy ACN News alt for new data privacy & cybersecurity regulatory changes. Every update since tracking began is archived, classified, and available as free RSS or email alerts — 10 changes logged to date.
What changed
ACN's CSIRT-ITA division published a security alert documenting CVE-2026-41259, a high-severity vulnerability in Mastodon's security mechanisms. The flaw enables a remote attacker to bypass authentication or security controls on affected servers. Affected system operators should immediately update to patched versions 4.3.22, 4.4.16, or 4.5.9 as directed by the Mastodon project maintainers. No specific compliance deadlines or penalties are stated in the advisory.
Organizations running Mastodon instances should prioritize patching given the high severity rating and remote exploitation potential. System administrators should verify current installed versions and apply updates through official Mastodon release channels referenced in the advisory.
What to do next
- Update Mastodon to version 4.3.22, 4.4.16, 4.5.9 or later per vendor security bulletin
Archived snapshot
Apr 25, 2026GovPing captured this document from the original source. If the source has since changed or been removed, this is the text as it existed at that time.
Rilevata vulnerabilità in Mastodon
**
Alert**
AL04/260424/CSIRT-ITA
Condividi
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Sintesi
Aggiornamenti di sicurezza sanano una vulnerabilità con gravità “alta” in Mastodon, social network server open source. Tale vulnerabilità, qualora sfruttata, potrebbe permettere a un utente malintenzionato remoto di eludere le funzionalità di sicurezza sui sistemi interessati.
Tipologia
- Security Feature Bypass
Prodotti e versioni affette
Mastodon
- 4.3.x, versioni precedenti alla 4.3.22
- 4.4.x, versioni precedenti alla 4.4.16
- 4.5.x, versioni precedenti alla 4.5.9
Azioni di mitigazione
In linea con le dichiarazioni del vendor, si raccomanda di aggiornare i prodotti vulnerabili seguendo le indicazioni del bollettino di sicurezza riportato nella sezione Riferimenti.
CVE (1)
Cerca:
| CVE | POC | EXPLOITATION |
| --- | --- | --- |
| CVE-2026-41259 | - | - |
Riferimenti (1)
Change log
| Versione | Note | Data |
|---|---|---|
| 1.0 | Pubblicato il 24-04-2026 | 24/04/2026 |
Impatto sistemico
Medio (63.46)
Argomenti
Data pubblicazione
24/04/26 ore 15:39
Data Ultimo Aggiornamento
24/04/26 ore 15:39
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