AI description
CVE-2026-42926 is an improper input handling vulnerability (CWE-172) affecting NGINX Open Source. This flaw manifests when NGINX is configured to proxy HTTP/2 traffic by setting `proxy_http_version` to 2 and simultaneously utilizes the `proxy_set_body` directive. Under these specific configuration parameters, an attacker can inject HTTP/2 frame headers and payload bytes into the traffic that is forwarded to the upstream peer. This issue primarily impacts the integrity of communications with the upstream server.
- 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.
- Source
- f5sirt@f5.com
- NVD status
- Analyzed
- Products
- nginx_gateway_fabric, nginx_open_source, nginx_instance_manager, nginx_ingress_controller
CVSS 4.0
- Type
- Secondary
- Base score
- 6.3
- Impact score
- -
- Exploitability score
- -
- Vector string
- CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Severity
- MEDIUM
CVSS 3.1
- Type
- Secondary
- Base score
- 5.8
- Impact score
- 1.4
- Exploitability score
- 3.9
- Vector string
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
- Severity
- MEDIUM
- f5sirt@f5.com
- CWE-172
- Hype score
- Not currently trending
Introducing ENDGINX - 5 CVEs in NGINX with open models. We let loose GLM 5.1 and 5.2 by @Zai_org on the NGINX codebase. The work resulted in six fixed vulnerabilities across five CVEs: CVE-2026-28755, CVE-2026-42926, CVE-2026-9256, CVE-2026-42055, and CVE-2026-42533. First of
@mufeedvh
27 Jul 2026
5971 Impressions
25 Retweets
74 Likes
42 Bookmarks
1 Reply
1 Quote
Nginx 1.31.0 Security Update - 6 CVEs Fixed CVE-2026-42945 - Heap buffer overflow in ngx_http_rewrite_module (potential code execution) CVE-2026-42926 - HTTP/2 request injection via proxy_set_body CVE-2026-42946 CVE-2026-42934 CVE-2026-40460 CVE-2026-40701 https://t.co/eRNItKkZ
@vutruso
15 May 2026
63 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
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