Heimdall: Path received via Envoy gRPC corrupted when containing query string

Exploitation

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

CVSS

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

EPSS

• CVE-2026-32811: 0.31% estimated exploitation activity in the next 30 days; percentile 24.14 (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 When using heimdall in envoy gRPC decision API mode, wrong encoding of the query URL string allows rules with non-wildcard path expressions to be bypassed. The HTTP based decision API is NOT affected, and proxy mode is NOT affected either. Note: The issue can only lead to unintended access if heimdall is configured with an "allow all" default rule. Since v0.16.0, heimdall enforces secure defaults and refuses to start with such a configuration unless this enforcement is explicitly disabled, e.g. via --insecure-skip-secure-default-rule-enforcement or the broader --insecure flag. Details Envoy splits the requested URL into parts, and sends the parts individually to heimdall. Although query and path are present in the API, the query field is documented to be always empty and the URL query is included in the path field [1]. The implementation uses go's url library to reconstruct the url which automatically encodes special characters in the path.…

Published by the source

18 Mar 2026, 13:00 UTC

Last modified by the source

20 Mar 2026, 21:19 UTC

Source last checked

26 Oct 2026, 15:18 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-r8x2-fhmf-6mxp

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# Patch Next advisory brief: CVE-2026-32811

Advisory: Heimdall: Path received via Envoy gRPC corrupted when containing query string
IDs: CVE-2026-32811, GHSA-r8x2-fhmf-6mxp
Record: https://patchnext.com/advisories/cve-2026-32811 (revision 1, source checked 26 Oct 2026, 15:18 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/dadrus/heimdall 0.17.11. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/dadrus/heimdall: affected >= 0.7.0-alpha, <= 0.17.10; fixed in 0.17.11

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

## 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 github.com/dadrus/heimdall.
- 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-r8x2-fhmf-6mxp (GitHub-reviewed advisory GHSA-r8x2-fhmf-6mxp lists affected ranges: Go github.com/dadrus/heimdall >=0.7.0-alpha <=0.17.10)

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