CVE-2026-53576
CriticalExploitedPublic exploitPrior to 1.0.45 and 1.3.21, the authentication filter for the REST API (@Filter("/api/v1/")) treats any request whose path ends in /configs as the public instance-config endpoint and forwards it without a credential check.
Published Jun 26, 2026 · Updated Aug 12, 2026 · Also known as EUVD-2026-39919, GHSA-2q47-568g-9h4f
Key Facts
Patch immediately- CVE-2026-53576 is a critical-severity vulnerability (CVSS 10.0 v3.1) affecting Kestra.
- It is exploited in the wild, listed in Industry KEV feed since Aug 1, 2026. Public exploit code is available.
- EPSS estimates a 3.3% probability of exploitation in the next 30 days.
- Fixed versions are available, including Kestra 1.0.45, Kestra 1.3.21.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
10.0
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
3.3%
Higher than 88.3% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2026-53576 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, the authentication filter for the REST API (@Filter("/api/v1/")) treats any request whose path ends in /configs as the public instance-config endpoint and forwards it without a credential check. kestra addresses its resources by URL path segments that the caller chooses (/api/v1/{tenant}/flows/{namespace}, /api/v1/{tenant}/executions/{namespace}/{id}, /api/v1/{tenant}/namespaces/{namespace}/kv/{key}). An anonymous caller picks the literal configs as the final segment, and the request bypasses Basic-Auth entirely. Because the bypass reaches the flow-create and execution-trigger routes, an unauthenticated caller creates a flow containing a Shell or Process task and runs it. The task executes as root inside the kestra container. The official docker-compose.yml mounts /var/run/docker.sock, so root in the container reaches the host Docker daemon. This vulnerability is fixed in 1.0.45 and 1.3.21.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Aug 1, 2026 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| KestraKestra | See advisory | 1.0.45 |
Patched Releases
Kestra
1.0.45, 1.3.21
Timeline
Publicly disclosed
Jun 26, 2026
Added to Industry KEV feed
Aug 1, 2026
Last updated
Aug 12, 2026
Weakness Type
- CWE-94 Improper Control of Generation of Code ('Code Injection')
- CWE-288 Authentication Bypass Using an Alternate Path or Channel
References
FAQ
Common Questions.
Kestra is an open-source, event-driven orchestration platform.
Affected: Kestra. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Aug 1, 2026.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Kestra 1.0.45, Kestra 1.3.21.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2026-53576 Running On Your Attack Surface?
Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.
Request A Demo