CVE-2026-33396
RCE in OneUptime prior to 10.0.35 via Playwright sandbox escape
Is CVE-2026-33396 being exploited?
Not confirmed. CVE-2026-33396 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 0.83% probability of exploitation in the next 30 days.
How severe is CVE-2026-33396?
CVE-2026-33396 is rated Critical with a CVSS score of 9.9. 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-2026-33396?
Yes. A fix has been recorded for CVE-2026-33396. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-33396 affect?
CVE-2026-33396 affects OneUptime Platform (pre-10.0.35), OneUptime Probe container. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-33396?
Patch to 10.0.35+
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
RCE: authenticated low-priv user can spawn arbitrary processes on Probe/host via Playwright sandbox escape.
Patch when possible
- affected< 10.0.35
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.