Dozzle's Cross-Site WebSocket Hijacking (CSWSH) on exec/attach endpointsbypasses authentication

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-44985: 0.21% estimated exploitation activity in the next 30 days; percentile 11.17 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary The WebSocket upgrader for the /exec and /attach endpoints uses CheckOrigin: func(r http.Request) bool { return true }, accepting upgrade requests from any origin. Combined with the JWT cookie using SameSite: Lax, this enables Cross-Site WebSocket Hijacking (CSWSH) — even when authentication is properly configured. An attacker hosting a page on a same-site origin (e.g., a sibling subdomain, or another service on localhost) can initiate a WebSocket connection to the exec endpoint that carries the victim's valid JWT cookie, gaining interactive shell access in any container the victim is authorized to access. Root cause 1. CheckOrigin bypassed (internal/web/terminal.go:15-21) The gorilla/websocket default CheckOrigin rejects cross-origin requests. Overriding it to return true removes the only server-side defense against CSWSH. 2. JWT cookie with SameSite=Lax (internal/web/auth.go:20-27) SameSite operates at the site level (eTLD+1), not the origin level. A page on…

Published by the source

11 May 2026, 14:07 UTC

Last modified by the source

8 Jun 2026, 23:35 UTC

Source last checked

26 Oct 2026, 15:23 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-j643-x8pv-8m67

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# Patch Next advisory brief: CVE-2026-44985

Advisory: Dozzle's Cross-Site WebSocket Hijacking (CSWSH) on exec/attach endpointsbypasses authentication
IDs: CVE-2026-44985, GHSA-j643-x8pv-8m67
Record: https://patchnext.com/advisories/cve-2026-44985 (revision 1, source checked 26 Oct 2026, 15:23 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/amir20/dozzle: affected <= 10.5.1

## Suggested inspection (read-only)
- Go github.com/amir20/dozzle: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/amir20/dozzle.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-j643-x8pv-8m67 (GitHub-reviewed advisory GHSA-j643-x8pv-8m67 lists affected ranges: Go github.com/amir20/dozzle >=0 <=10.5.1)

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