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TI-2026-38637 Aliases CVE-2026-53576

Kestra: Unauthenticated RCE via /configs path-suffix auth-filter bypass

Priority HIGH 82CWE-288Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass, Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-288 and CWE-94.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.03296 88th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed kestra (kestra-io): 1.0.45, 1.3.21

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Kestrakestrabefore 1.0.45; 1.1.0 to before 1.3.211.0.45, 1.3.21Patch availableCNA
  • kestra VendorKestra Affected before 1.0.45; 1.1.0 to before 1.3.21 Fixed in 1.0.45, 1.3.21 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:kestra:kestra:*:*:*:*:*:*:*:*before 1.0.45; 1.1.0 to before 1.3.21VulnerableKestra
  • cpe:2.3:a:kestra:kestra:*:*:*:*:*:*:*:* Versions before 1.0.45; 1.1.0 to before 1.3.21 Vulnerable ·Kestra

Remediation

  • Fix · CNA kestra (kestra-io) Fixed in 1.0.45, 1.3.21

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-53576

References

Exploit 1

  • TI-2026-36769 Kestra: Unauthenticated Remote Code Execution via Authentication Bypass in `AuthenticationFilter` KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-28138 Kestra v1.3.3 and before is vulnerable to SQL Injection. CVSS 3.1CRITICAL 9.8
  • TI-2026-26858 Kestra: Remote Code Execution via SQL Injection CVSS 3.1CRITICAL 10.0
  • TI-2026-39775 Kestra BasicAuth Password Stored as SHA-512 Enables Offline Brute-Force Attack CVSS 3.1HIGH 8.7
  • TI-2026-36817 Information disclosure in kestra CVSS 3.1HIGH 7.7
  • TI-2026-33542 Kestra: Path traversal via URL-encoded "%2E%2E" in execution and namespace file endpoints allows arbitrary file read CVSS 3.1HIGH 7.7
See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences