Use of the backend-facing $scheme variable in the trailing-slash directory redirect in nginx.conf of Chainguard Academy (edu) from commit 0b75ff98057f69b044a3e7194e428066ac5ad0d4 before commit 93dc0e50739c225f5aee2e803800a47fc0feb906 allows an on-path network attacker to read or modify documentation content served to a victim via an HTTPS request for a slashless directory path, because TLS terminates at the load balancer in front of Nginx and the resulting 301 response redirects the client to a plaintext http:// URL. Browsers that ship the HSTS preload list are not affected, because the .dev top-level domain is preloaded; clients that do not enforce HSTS, such as command-line HTTP clients and scripts that follow redirects, are affected.
History

Tue, 06 Oct 2026 21:15:00 +0000

Type Values Removed Values Added
First Time appeared Chainguard
Chainguard chainguard Academy (edu)
Vendors & Products Chainguard
Chainguard chainguard Academy (edu)

Tue, 06 Oct 2026 14:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 05 Oct 2026 20:15:00 +0000

Type Values Removed Values Added
Description Use of the backend-facing $scheme variable in the trailing-slash directory redirect in nginx.conf of Chainguard Academy (edu) from commit 0b75ff98057f69b044a3e7194e428066ac5ad0d4 before commit 93dc0e50739c225f5aee2e803800a47fc0feb906 allows an on-path network attacker to read or modify documentation content served to a victim via an HTTPS request for a slashless directory path, because TLS terminates at the load balancer in front of Nginx and the resulting 301 response redirects the client to a plaintext http:// URL. Browsers that ship the HSTS preload list are not affected, because the .dev top-level domain is preloaded; clients that do not enforce HSTS, such as command-line HTTP clients and scripts that follow redirects, are affected.
Title Chainguard Academy (edu) Nginx directory redirect downgrades HTTPS requests to HTTP
Weaknesses CWE-319
References
Metrics cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 2.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: chainguard

Published: 2026-10-05T19:45:50.015Z

Updated: 2026-10-06T13:44:09.303Z

Reserved: 2026-10-05T19:21:04.930Z

Link: CVE-2026-105766

cve-icon Vulnrichment

Updated: 2026-10-06T13:43:56.582Z

cve-icon NVD

Status : Deferred

Published: 2026-10-05T20:17:20.620

Modified: 2026-10-06T15:03:59.427

Link: CVE-2026-105766

cve-icon Redhat

No data.