Argo has Missing Authorization in its Sync ConfigMap Provider

Exploitation

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

CVSS 4.0

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

EPSS

• CVE-2026-42297: 0.52% estimated exploitation activity in the next 30 days; percentile 43.93 (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 Sync Service's ConfigMap-backed provider (server/sync/synccm.go) performs zero authorization checks on all CRUD operations (create, read, update, delete). Any authenticated user — including those using fake Bearer tokens — can create, read, update, and delete Kubernetes ConfigMaps containing synchronization limits. Details The ConfigMap-backed provider (server/sync/synccm.go) has no auth.CanI checks: - server/sync/synccm.go — lines 23-155 - All four SyncService endpoints: CreateSyncLimit, GetSyncLimit, UpdateSyncLimit, DeleteSyncLimit PoC Prerequisites - Argo Server running with --auth-mode=server - Port-forward: kubectl port-forward -n argo svc/argo-server 2746:2746 Step 1: Create Sync Limit (Fake Token) Result: {"namespace":"default","cmName":"test-sync","key":"test-key","limit":5} Verify ConfigMap was created in Kubernetes: Step 2: Read Sync Limit (Fake Token) Result: {"namespace":"default","cmName":"test-sync","key":"test-key","limit":5} Step 3: Update Sync Limit…

Published by the source

4 May 2026, 20:00 UTC

Last modified by the source

13 May 2026, 13:39 UTC

Source last checked

26 Oct 2026, 15:20 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-xchc-cqwg-g76q

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-42297

Advisory: Argo has Missing Authorization in its Sync ConfigMap Provider
IDs: CVE-2026-42297, GHSA-xchc-cqwg-g76q
Record: https://patchnext.com/advisories/cve-2026-42297 (revision 1, source checked 26 Oct 2026, 15:20 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/argoproj/argo-workflows/v4 4.0.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/argoproj/argo-workflows/v4: affected >= 4.0.0, < 4.0.5; fixed in 4.0.5

## Suggested inspection (read-only)
- Go github.com/argoproj/argo-workflows/v4: 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/argoproj/argo-workflows/v4.
- 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-xchc-cqwg-g76q (GitHub-reviewed advisory GHSA-xchc-cqwg-g76q lists affected ranges: Go github.com/argoproj/argo-workflows/v4 >=4.0.0 <4.0.5)

Commands are suggestions: review each one before running it.