CVE-2026-33210
Ruby JSON gem format string injection enables DoS or data disclosure.
Is CVE-2026-33210 being exploited?
Not confirmed. CVE-2026-33210 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 0.86% probability of exploitation in the next 30 days.
How severe is CVE-2026-33210?
CVE-2026-33210 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-2026-33210?
Yes. A fix has been recorded for CVE-2026-33210. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-33210 affect?
CVE-2026-33210 affects Ruby JSON gem (versions < 2.15.2.1, < 2.17.1.2, < 2.19.2). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-33210?
Upgrade to patched versions (>=2.15.2.1, >=2.17.1.2, >=2.19.2).
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
DoS or information disclosure via format string injection when parsing with allow_duplicate_key: false.
Patch when possible
- affected>= 2.14.0 and < 2.15.2.1
- affected>= 2.16.0 and < 2.17.1.2
- affected>= 2.18.0 and < 2.19.2
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.