CVE-2026-23962
7.5 · HIGHOverview
CVE-2026-23962 is a high-severity vulnerability affecting joinmastodon mastodon. It was published on January 22, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Mastodon is a free, open-source social network server based on ActivityPub. Mastodon versions before v4.3.18, v4.4.12, and v4.5.5 do not have a limit on the maximum number of poll options for remote posts, allowing attackers to create polls with a very large amount of options, greatly increasing resource consumption. Depending on the number of poll options, an attacker can cause disproportionate resource usage in both Mastodon servers and clients, potentially causing Denial of Service either server-side or client-side. Mastodon versions v4.5.5, v4.4.12, v4.3.18 are patched.
Remediation
Check the references section for vendor advisories and patches from joinmastodon. Update mastodon to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| joinmastodon | mastodon | >= 0, < 4.3.18 | Affected |
Frequently Asked Questions
What is CVE-2026-23962?
CVE-2026-23962 is a high-severity vulnerability affecting joinmastodon mastodon. It was published on January 22, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-23962?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-23962?
Check the references section for vendor advisories and patches from joinmastodon. Update mastodon to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-23962?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-23962 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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