CVE-2026-42926mediumCWE-172

CVE-2026-42926: medium-severity vulnerability in F5 NGINX Open Source

NGINX ngx_http_proxy_v2_module vulnerability

Published

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 6.3epss 0.3%
from disclosure to weapon24 days
Published on NVDMay 13
1st PoC+24d
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:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N
Affected products
F5 · NGINX Open Source
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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