Affects widely used NGINX Open Source/Plus; potential web service disruption from worker crashes.
CVE-2026-27654
Buffer overflow in NGINX MOVE/COPY (DAV) may crash worker or alter filenames outside doc root.
Is CVE-2026-27654 being exploited?
Not confirmed. CVE-2026-27654 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 25% probability of exploitation in the next 30 days.
How severe is CVE-2026-27654?
CVE-2026-27654 is rated High with a CVSS score of 8.8. 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-2026-27654?
Yes. A fix has been recorded for CVE-2026-27654. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-27654 affect?
CVE-2026-27654 affects NGINX Open Source, NGINX Plus, ngx_http_dav_module. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-27654?
Patch when available; disable MOVE/COPY if not needed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Crashes NGINX worker or tampers filenames outside document root via crafted MOVE/COPY in the DAV module; potential DoS, low-privilege context.
Patch when possible
- affected>= 1.29.0 and < 1.29.7
- affected>= 0.5.13 and < 1.28.3
- affected>= R36 and < R36 P3
- affected>= R35 and < R35 P2
- affected>= R34 and < *
- affected>= R33 and < *
- affected>= R32 and < R32 P5
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.