CVE-2026-42926 (GCVE-0-2026-42926)

Vulnerability from cvelistv5 – Published: 2026-05-13 14:12 – Updated: 2026-05-13 16:16
VLAI?
Title
NGINX ngx_http_proxy_v2_module vulnerability
Summary
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.
Severity ?
5.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
6.3 (Medium)
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
CWE
Assigner
f5
References
URL Tags
https://my.f5.com/manage/s/article/K000161131 vendor-advisorypatch
Impacted products
Vendor Product Version
F5 NGINX Open Source Unaffected: 1.31.0 , < * (semver)
Affected: 1.29.4 , < 1.30.1 (semver)
Create a notification for this product.
Date Public ?
2026-05-13 14:00
Credits
F5 acknowledges Mufeed VH of Winfunc Research, Hcamael of aipyaipy, and 章鱼哥 of aipyaipy for bringing this issue to our attention and following the highest standards of coordinated disclosure.
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.