CVE-2026-73247

Received Received - Intake

Remote Code Execution in Kestra Prior to 2.0.0

Publication date: 2026-08-11

Last updated on: 2026-08-13

Assigner: GitHub, Inc.

Description

Kestra is an open-source, event-driven orchestration platform. Prior to 2.0.0, Kestra's core/src/main/java/io/kestra/core/runners/pebble/functions/HttpFunction.java passes the user-controlled http() uri argument to URI.create() and the server-side HTTP client without restricting private, loopback, or link-local destinations, allowing an unauthenticated attacker to import and execute a flow that accesses internal services or cloud metadata.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-11

Last Modified

2026-08-13

Generated

2026-09-01

AI Q&A

2026-08-12

EPSS Evaluated

2026-08-30

NVD

CVE-2026-73247

Affected Vendors & Products

Vendor	Product	Version / Range
kestra	kestra	to 2.0.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-918	The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Attack-Flow Graph

Executive Summary

This vulnerability in Kestra versions before 2.0.0 allows unauthenticated attackers to use the http() function in flows to access internal services or cloud metadata by passing user-controlled URIs to URI.create(). The function does not restrict connections to private, loopback, or link-local destinations.

Detection Guidance

This vulnerability allows unauthenticated access to internal services or cloud metadata via HTTP requests. To detect it, monitor outbound HTTP requests from Kestra instances, especially those targeting private, loopback, or link-local IP addresses (e.g., 127.0.0.0/8, 169.254.0.0/16, 10.0.0.0/8). Check Kestra logs for suspicious http() function calls in flows.

Impact Analysis

An attacker could exploit this to access sensitive internal services, exfiltrate data from cloud metadata services, or interact with restricted APIs. This could lead to data breaches, unauthorized access to systems, or lateral movement within a network.

Compliance Impact

This vulnerability could lead to unauthorized data access or exfiltration, violating GDPR's data protection principles or HIPAA's security requirements for protected health information. Organizations using affected Kestra versions may face compliance violations and penalties.

Mitigation Strategies

Upgrade Kestra to version 2.0.0 or later to address the vulnerability in the HTTP function handling.

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