CVE-2026-1642

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://my.f5.com/manage/s/article/K000159824
http://www.openwall.com/lists/oss-security/2026/02/05/1

Configurations

No configuration.

History

05 Feb 2026, 06:15

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/02/05/1 -

04 Feb 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-04 15:16

Updated : 2026-02-05 06:15

NVD link : CVE-2026-1642

Mitre link : CVE-2026-1642

CVE.ORG link : CVE-2026-1642

JSON object : View

Products Affected

No product.

CWE

CWE-349

Acceptance of Extraneous Untrusted Data With Trusted Data

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