CVE-2026-82404
Prototype pollution in TOON allows DoS and potential RCE when decoding untrusted data.
Is CVE-2026-82404 being exploited?
Not confirmed. CVE-2026-82404 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.40% probability of exploitation in the next 30 days.
How severe is CVE-2026-82404?
CVE-2026-82404 is rated High with a CVSS score of 8.3. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-82404?
Yes. A fix has been recorded for CVE-2026-82404. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-82404 affect?
CVE-2026-82404 affects toon < 2.3.1, Services decoding untrusted TOON payloads, Node.js/JavaScript runtimes using toon. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-82404?
Upgrade to toon v2.3.1 and sanitize/untrusted inputs
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Attacker-controlled TOON can pollute Object.prototype during decode, causing denial of service or enabling remote code execution if a gadget exists.
Immediate action required
- affected< 2.3.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.