Vulnerability Description
When NGINX Open Source is configured to proxy HTTP/2 traffic by setting proxy_http_version to 2, and also uses proxy_set_body, an attacker may be able to inject frame headers and payload bytes to the upstream peer. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| F5 | Nginx Gateway Fabric | >= 1.3.0, <= 1.6.2 |
| F5 | Nginx Open Source | >= 1.29.4, <= 1.30.0 |
| F5 | Nginx Instance Manager | >= 2.16.0, <= 2.22.0 |
| F5 | Nginx Ingress Controller | >= 3.5.0, <= 3.7.2 |
Related Weaknesses (CWE)
References
- https://my.f5.com/manage/s/article/K000161131MitigationVendor Advisory
FAQ
What is CVE-2026-42926?
CVE-2026-42926 is a vulnerability with a CVSS score of 5.8 (MEDIUM). When NGINX Open Source is configured to proxy HTTP/2 traffic by setting proxy_http_version to 2, and also uses proxy_set_body, an attacker may be able to inject frame headers and payload bytes to the ...
How severe is CVE-2026-42926?
CVE-2026-42926 has been rated MEDIUM with a CVSS base score of 5.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42926?
Check the references section above for vendor advisories and patch information. Affected products include: F5 Nginx Gateway Fabric, F5 Nginx Open Source, F5 Nginx Instance Manager, F5 Nginx Ingress Controller.