Repository Credentials Race Condition Crashes Argo CD Server

Summary

A race condition in the repository credentials handler can cause the Argo CD server to panic and crash when concurrent operations are performed on the same repository URL.

Details

The vulnerability is located in numerous repository related handlers in the util/db/repository_secrets.go file. For example, in the secretToRepoCred function. The issue manifests as a concurrent map access panic:

concurrent map read and map write
...
goroutine 1104 [running]:
github.com/argoproj/argo-cd/v2/util/db.(*secretsRepositoryBackend).secretToRepoCred(0xc000e50ea8?, 0xc000c65540)
        /go/src/github.com/argoproj/argo-cd/util/db/repository_secrets.go:404 +0x31e

The race condition occurs due to:

1. Concurrent repository credential operations (create/update/delete) accessing the same map
2. Kubernetes informer re-syncs happening simultaneously
3. Background watchers updating the same secret data
4. No mutex protection for map access

A valid API token with repositories resource permissions (create, update, or delete actions) is required to trigger the race condition.

Impact

This vulnerability causes the entire Argo CD server to crash and become unavailable. Attackers can repeatedly and continuously trigger the race condition to maintain a denial-of-service state, disrupting all GitOps operations. Default ArgoCD configuration is vulnerable.

The affected code was originally introduced in PR #6103 and released in v2.1.0.

This data race was addressed by deep-copying the Secret objects before reading/writing.

Credits

This vulnerability was found, reported and fixed by:

@thevilledev

The Argo team would like to thank him for his responsible disclosure and constructive communications during the resolve of this issue.