CVE•Published 2026-04-23•Modified 2026-04-24•0 articles on news•5 live references•NVD data
CVE-2026-41259
Vulnerability data via NVD (ingested)
CVSS v3.1
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EPSS percentile
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Weaknesses (CWE)
Description
Mastodon is a free, open-source social network server based on ActivityPub. Prior to v4.5.9, v4.4.16, and v4.3.22, Mastodon allows restricting new user sign-up based on e-mail domain names, and performs basic validation on e-mail addresses, but fails to restrict characters that are interpreted differently by some mailing servers. This vulnerability is fixed in v4.5.9, v4.4.16, and v4.3.22.
Timeline
Published 2026-04-23
Modified 2026-04-24
External references
Search for exposed instances
Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common). Live host counts are a Premium feature.
More intel sources (5)
Shodan report
vuln:CVE-2026-41259Country / ASN / product breakdown for the vuln query.
Censys
vulnerabilities.cve_id: CVE-2026-41259Censys host search filtered to this CVE id.
grep.app
CVE-2026-41259Public source-code mentions — fast PoC discovery.
GitHub code
CVE-2026-41259GitHub code search for direct mentions.
Google dork
"CVE-2026-41259" exploit -site:nvd.nist.govWrite-ups and news, NVD excluded.
Known PoCs on GitHub
No public proof-of-concept repositories found for CVE-2026-41259 on GitHub.
We haven't classified any articles referencing CVE-2026-41259 yet. The external references above still apply.