CVE-2026-42926 NGINX ngx_http_proxy_v2_module vulnerability
Attackers can inject frame headers and payload bytes to upstream peers when NGINX proxies HTTP/2 traffic with specific body settings.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-42926?
CVE-2026-42926 is a medium-severity vulnerability in F5 NGINX Open Source, published on 13 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-172
Which versions are affected by CVE-2026-42926?
2 open source packages ship an affected version, including nginx and nginx-gateway. It affects 4 products.
| Package | Affected | Fixed in |
|---|---|---|
nginx Bitnami | From 1.29.4 | 1.30.1 |
nginx-gateway Bitnami | From 1.29.4 | 1.30.1 |
Products include F5 Nginx Gateway Fabric, F5 Nginx Ingress Controller, F5 Nginx Instance Manager, F5 Nginx Open Source.
How do I fix CVE-2026-42926?
Upgrade nginx to 1.30.1 or later.
Is CVE-2026-42926 being exploited?
There is no known exploitation of CVE-2026-42926 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in F5 NGINX Open Source
Sources
Also known as BIT-nginx-2026-42926, BIT-nginx-gateway-2026-42926, DEBIAN-CVE-2026-42926, ECHO-64e0-d4ec-3b8b, GHSA-v43f-895r-chhh, MINI-5gj3-wj3v-54w5 and 1 more.