Cyber Resilience

CVE-2026-53577

Access Control in Kestra ≤ 1.0.45

Public PoCAccess Control
Published
26 June 2026
Modified
01 July 2026
Patch / advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0031 24th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-53577 is a medium-severity Incorrect Authorization (CWE-863) vulnerability in Kestra Kestra. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 24th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, the previewFileFromExecution endpoint (GET /api/v1/{tenant}/executions/{executionId}/file/preview) contains an access control bypass that allows any authenticated user to read output files from any other execution within the same tenant, bypassing…

more

execution-level and namespace-level isolation. This vulnerability is fixed in 1.0.45 and 1.3.21.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
Why these techniques?

Authorization bypass directly enables unauthorized read access to execution output files stored on the system.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-45807Same product: Kestra Kestra
CVE-2026-55069Same product: Kestra Kestra
CVE-2026-34612Same product: Kestra Kestra
CVE-2026-33664Same product: Kestra Kestra
CVE-2026-49869Same product: Kestra Kestra
CVE-2026-29082Same product: Kestra Kestra
CVE-2026-53576Same product: Kestra Kestra
CVE-2026-38428Same product: Kestra Kestra
CVE-2026-49984Same product: Kestra Kestra
CVE-2026-65054Shared CWE-863

Affected Assets

kestra
kestra
≤ 1.0.45 · 1.1.0 — 1.3.21

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-6 Least Privilege
  • AC-4 Information Flow Enforcement
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces authorization checks on the previewFileFromExecution endpoint to block cross-execution file reads within a tenant.

prevent

Limits user privileges so authenticated accounts cannot access execution outputs outside their assigned namespace or execution scope.

prevent

Enforces information flow policies that isolate execution file outputs and prevent unauthorized data leakage between executions.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.

prevents

Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.

prevents

By tying access rights to identity, device, location and classification, the control reduces the likelihood that an authorization decision will be based on an incorrect or bypassed policy.

References