Glances's REST/WebUI Lacks Host Validation and Remains Exposed to DNS Rebinding

Exploitation

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

CVSS

5.9 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:L/A:N

EPSS

• CVE-2026-32632: 0.19% estimated exploitation activity in the next 30 days; percentile 8.89 (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 Glances recently added DNS rebinding protection for the MCP endpoint, but the main REST/WebUI FastAPI application still accepts arbitrary Host headers and does not apply TrustedHostMiddleware or an equivalent host allowlist. As a result, the REST API, WebUI, and token endpoint remain reachable through attacker-controlled domains in classic DNS rebinding scenarios. Once the victim browser has rebound the attacker domain to the Glances service, same-origin policy no longer protects the API because the browser considers the rebinding domain to be the origin. This is a distinct issue from the previously reported default CORS weakness. CORS is not required for exploitation here because DNS rebinding causes the victim browser to treat the malicious domain as same-origin with the rebinding target. Details The MCP endpoint now has explicit host-based transport security: However, the main FastAPI application for REST/WebUI/token routes is initialized without any host validation…

Published by the source

16 Mar 2026, 16:34 UTC

Last modified by the source

13 Jul 2026, 07:26 UTC

Source last checked

26 Oct 2026, 13:37 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-hhcg-r27j-fhv9

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-hhcg-r27j-fhv9

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# Patch Next advisory brief: CVE-2026-32632

Advisory: Glances's REST/WebUI Lacks Host Validation and Remains Exposed to DNS Rebinding
IDs: CVE-2026-32632, GHSA-hhcg-r27j-fhv9
Record: https://patchnext.com/advisories/cve-2026-32632 (revision 2, source checked 26 Oct 2026, 13:37 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: glances 4.5.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI glances: affected < 4.5.2; fixed in 4.5.2

## Suggested inspection (read-only)
- `python -m pip show glances`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on glances.
- 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://osv.dev/vulnerability/GHSA-hhcg-r27j-fhv9 (OSV record GHSA-hhcg-r27j-fhv9 lists affected ranges: PyPI glances >=0 <4.5.2 (fixed))
- Verified: https://github.com/advisories/GHSA-hhcg-r27j-fhv9 (GitHub-reviewed advisory GHSA-hhcg-r27j-fhv9 lists affected ranges: PyPI glances >=0 <4.5.2)

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