CVE-2026-105766 json
Chainguard Academy (edu) Nginx directory redirect downgrades HTTPS requests to HTTP
published last mo. modified last mo. also EUVD-2026-92778
- cvss
- 3.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 1%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- github.com/chainguard-dev/edu@93dc0e5 commit
- github.com/chainguard-dev/edu#3989 pull request
Is CVE-2026-105766 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.11% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 2.3 | 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 |
| CNA | 3.1 | 3.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N |
| CNA | 4.0 | 2.3 | 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/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 |
Affected products
- Chainguard Chainguard Academy (edu)
Classification
- Weakness
-
- CWE-319 Cleartext Transmission of Sensitive Information
References
Sources
- CVE List CVE-2026-105766
- NVD CVE-2026-105766
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.