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UnratedPublic exploit

Unauthenticated RCE in Kestra REST API via /configs authentication bypass

IdentifiersCVE-2026-53576CWE-288

CVE-2026-53576 is a critical authentication-bypass vulnerability in Kestra, an open-source event-driven orchestration platform. In versions prior to 1.0.45 and 1.3.21, the REST API authentication filter for @Filter("/api/v1/**") incorrectly treats any request whose path ends with /configs as the public instance-config endpoint and forwards the request without enforcing Basic Authentication. Because Kestra resource routing uses caller-controlled URL path segments, an unauthenticated attacker can craft API paths whose final segment is the literal string "configs" to reach protected endpoints without credentials. The bypass can be used against flow-creation and execution-trigger routes, allowing an anonymous attacker to create a malicious flow containing a Shell or Process task and then execute it. The task runs as root inside the Kestra container. In deployments using the official docker-compose configuration, where /var/run/docker.sock is mounted into the container, this can be chained into access to the host Docker daemon and potential host compromise.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation provides unauthenticated remote code execution in the Kestra environment. An attacker can create and run arbitrary Shell or Process tasks as root inside the Kestra container, resulting in full compromise of the application runtime, arbitrary command execution, data access and modification, and service disruption. In default Docker-based deployments that expose /var/run/docker.sock to the container, root execution inside the container can be leveraged to control the host Docker daemon, enabling container escape in practice and full host-level compromise with corresponding confidentiality, integrity, and availability impact.

Mitigation

If you can’t patch tonight, do this now.

If immediate patching is not possible, restrict network access to the Kestra REST API so unauthenticated external users cannot reach /api/v1/* endpoints, place the service behind a trusted reverse proxy or access-control layer, and monitor for suspicious anonymous requests whose paths end in /configs. As a defense-in-depth measure, avoid mounting /var/run/docker.sock into the Kestra container unless strictly required, because that mount materially increases post-exploitation impact from container-level root to host-level compromise.

Remediation

Patch, then assume compromise.

Upgrade Kestra to a fixed release. The vulnerability is addressed in versions 1.0.45 and 1.3.21. Users should update to 1.0.45 or later on the 1.0 branch, or 1.3.21 or later on the 1.3 branch, and ensure all exposed Kestra instances are running a patched version.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

ACTIVITY FEED

Recent activity

7 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

7 SOURCESView more in app
What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity6

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES
MITRE CVE
cve.org · CVE-2026-53576
NVD
nvd.nist.gov/vuln/detail/CVE-2026-53576
MITRE CWE · CWE-288
cwe.mitre.org