CVE-2026-1642 describes a medium-severity vulnerability in NGINX OSS and NGINX Plus, as well as several related F5 products, when configured to proxy to upstream TLS servers. A man-in-the-middle attacker on the upstream side could potentially inject plaintext data into the proxied server's response, though this requires specific conditions beyond the attacker's control. The CVSS score of 5.9 reflects a network attack vector with high attack complexity, leading to a high impact on integrity but no impact on confidentiality or availability. There is no evidence of active exploitation, public exploit code, or inclusion in the CISA KEV catalog, though it has garnered some community discussion and media coverage.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
>= 1.2.0, <= 1.6.2CPE matchmatch criteria | cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:* | ||
>= 2.0.0, < 2.4.1CPE matchmatch criteria | cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:* | ||
>= 3.4.0, <= 3.7.2CPE matchmatch criteria | cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:* | ||
>= 4.0.0, <= 4.0.1CPE matchmatch criteria | cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:* | ||
>= 5.0.0, < 5.3.3CPE matchmatch criteria | cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:* |
CVSS version used by this source: 4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.2 GitHub mentions.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
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