NGINX vulnerability_CVE-2026-1642

5.9 / 10

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Description

A vulnerability exists in NGINX OSS and NGINX Plus when configured to proxy to upstream Transport Layer Security (TLS) servers. An attacker with a man-in-the-middle (MITM) position on the upstream server side—along with conditions beyond the attacker's control—may be able to inject plain text data into the response from an upstream proxied server. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Basic Information

ID CVE-2026-1642

Source f5

Published Feb 4, 2026 at 15:02

Modified Feb 4, 2026 at 16:02

Affected Product

Vendor F5

Product NGINX Open Source

Version 1.3.0

Affected Versions F5 NGINX Open Source 1.3.0
F5 NGINX Plus R36
F5 NGINX Plus R35
F5 NGINX Plus R34
F5 NGINX Plus R33
F5 NGINX Plus R32

CWE Classification

CWE-349

References

my.f5.com /manage/s/article/K000159824

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    "published": "2026-02-04T15:02:06.154Z",
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