CVE-2026-97205 F5 CVE debrief

Who should care

Defenders responsible for NGINX Plus and NGINX Open Source deployments should assess exposure, especially where AIO is enabled. System administrators and security teams should verify versions and configurations, and consider the feasibility of ASLR bypass.

Why it matters

This vulnerability in NGINX ngx_http_core_module requires attention from defenders of NGINX Plus and NGINX Open Source deployments, especially where asynchronous file I/O (AIO) is enabled. The vulnerability may allow remote attackers to cause a denial-of-service (DoS), corrupt memory, or potentially trigger code execution on systems with Address Space Layout Randomization (ASLR) disabled or when ASLR can be bypassed. Defenders should verify exposure, assess AIO configurations, and consider compensating controls.

• Potential for remote denial-of-service (DoS) on NGINX systems
• Memory corruption or worker process crashes
• Possible code execution on systems with ASLR disabled or when ASLR can be bypassed
• Need for verification of exposure in NGINX Plus and NGINX Open Source deployments

Technical summary

The vulnerability exists in the ngx_http_core_module module of NGINX Plus and NGINX Open Source. When AIO is enabled, processing SSI pages with 'include virtual' commands can trigger a UAF, leading to memory corruption or worker process crashes. Code execution is possible on systems with ASLR disabled or when ASLR can be bypassed. The vulnerability requires attention from defenders of NGINX Plus and NGINX Open Source deployments, especially where AIO is enabled. Defenders should verify exposure, assess AIO configurations, and consider compensating controls.

Defensive priority

Defenders should prioritize verifying exposure in NGINX Plus and NGINX Open Source deployments, especially where AIO is enabled, and assess the feasibility of ASLR bypass.

Recommended defensive actions

• Verify NGINX Plus and NGINX Open Source versions to determine exposure
• Assess AIO configuration and potential for ASLR bypass
• Review vendor advisory for additional mitigation guidance
• Consider compensating controls for systems with ASLR disabled
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE Program record and NVD vulnerability detail provide official information on the vulnerability. The vendor advisory from F5 offers additional context. The vulnerability exists in the ngx_http_core_module module of NGINX Plus and NGINX Open Source. When AIO is enabled, processing SSI pages with 'include virtual' commands can trigger a UAF, leading to memory corruption or worker process crashes. Code execution is possible on systems with ASLR disabled or when ASLR can be bypassed. Defenders should verify exposure in NGINX Plus

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.