Bug 2436738 (CVE-2026-1642)

Summary: CVE-2026-1642 nginx: NGINX: Data injection via man-in-the-middle attack on TLS proxied connections
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: caswilli, kaycoth
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in NGINX. When NGINX is 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.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2436870, 2436871    
Bug Blocks:    

Description OSIDB Bzimport 2026-02-04 16:01:15 UTC
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.

Comment 3 errata-xmlrpc 2026-03-03 11:27:19 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:3638 https://access.redhat.com/errata/RHSA-2026:3638