# CVE-2026-73247: Kestra Server-Side Request Forgery via Pebble http() function

Source: https://junglewise.ai/threats/cve-2026-73247-kestra-server-side-request-forgery-via-pebble-http-function  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-11. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-73247 · Severity: high · CVSS 8.6 · Published 2026-08-11

Kestra, an open-source workflow orchestration platform, contains a vulnerability in its Pebble template engine that allows attackers to make arbitrary HTTP requests to internal services and cloud metadata endpoints without authentication. An attacker can import a malicious workflow and retrieve sensitive cloud credentials (AWS/GCP/Azure), access internal services, or interact with localhost endpoints, potentially leading to credential theft and lateral movement within cloud environments.

Technologies: [Kestra](https://junglewise.ai/threats/technologies/kestra). Vendors: [Kestra](https://junglewise.ai/threats/vendors/kestra), [Maven](https://junglewise.ai/threats/vendors/maven).

## Quick answers

**Is CVE-2026-73247 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-73247 being exploited in the wild.

**How severe is CVE-2026-73247?** High severity, with a CVSS score of 8.6, published 11 August 2026.

**Which products and versions are affected?** Kestra all versions (OSS); io.kestra:core (Maven) <= 1.3.31, ECOSYSTEM:introduced=0,last_affected=1.3.31; io.kestra:kestra-core (Maven) < 2.0.0, ECOSYSTEM:introduced=0,fixed=2.0.0.

**Is there a fix for CVE-2026-73247?** Yes. io.kestra:kestra-core (Maven): upgrade to 2.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-73247 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-73247?** Check whether you run Kestra, io.kestra:core (Maven) or io.kestra:kestra-core (Maven) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- io.kestra:kestra-core (Maven): upgrade to 2.0.0 or later

  ```sh
  # set io.kestra:kestra-core to 2.0.0 in your pom.xml or build.gradle
  ```


## Technical details

The vulnerability is a Server-Side Request Forgery (SSRF) in the Pebble template engine's http() function (HttpFunction.java, lines 77–106). The root cause is the lack of URL validation: user-supplied URLs are passed directly to URI.create() without checks for private IP ranges (10.0.0.0/8, 192.168.0.0/16, 127.0.0.1), cloud metadata endpoints (169.254.169.254), or restricted URL schemes (file://, gopher://). Additionally, no authentication is enforced beyond a basic tenant check for "main", and the HttpFunction is unconditionally registered. An unauthenticated attacker can import a malicious workflow YAML file and execute it to trigger HTTP requests from the server, bypassing network perimeter controls to access internal systems and metadata services.

## Affected products

- Kestra Kestra all versions (OSS)

## Identifiers

- CVE-2026-73247
- GHSA-r56g-q4p6-m3p6

## Timeline

- 2026-09-17: disclosed: Advisory GHSA-r56g-q4p6-m3p6 published

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