CVE-2026-27784
32-bit NGINX Open Source mp4_module mem over-read/write via crafted MP4; may crash worker.
Is CVE-2026-27784 being exploited?
Not confirmed. CVE-2026-27784 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 1.0% probability of exploitation in the next 30 days.
How severe is CVE-2026-27784?
CVE-2026-27784 is rated High with a CVSS score of 8.5. 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-2026-27784?
Yes. A fix has been recorded for CVE-2026-27784. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-27784 affect?
CVE-2026-27784 affects NGINX Open Source (32-bit) with ngx_http_mp4_module and mp4 directive. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-27784?
Patch when available or disable mp4_module as workaround
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote memory corruption via crafted MP4 can crash NGINX worker, causing service disruption.
Patch when possible
- affected>= 1.29.0 and < 1.29.7
- affected>= 1.1.19 and < 1.28.3
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.