Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-73247 – Unauthenticated SSRF – Kestra prior to 2.0.0

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-73247 is a Server-Side Request Forgery (SSRF) vulnerability in Kestra’s Pebble templating engine, specifically in the http() function used by imported Flow definitions. An unauthenticated attacker can craft or import a malicious Flow YAML that causes the Kestra server to make requests to internal services or cloud metadata endpoints. The flaw carries a CVSS v3.1 score of 8.6 (High).

Technical details

  • Root cause: the Pebble http() function passes user-supplied input directly to URI.create() without validating destination hosts or schemes.
  • No filtering exists for private/internal address ranges (e.g., 10.0.0.0/8, 192.168.0.0/16) or the cloud metadata address 169.254.169.254.
  • Unrestricted URI schemes (such as file:// and gopher://) are permitted, expanding potential impact beyond standard HTTP SSRF.
  • Attack vector: network, no authentication or privileges required, no user interaction needed — an attacker only needs to import/execute a crafted Flow.
  • Impact: the server can be coerced into accessing internal-only services or cloud instance metadata, resulting in high confidentiality impact (information disclosure); integrity and availability are not directly affected per the CVSS vector.

Affected software

  • Kestra: all versions prior to 2.0.0

Severity

  • CVSS v3.1 Base Score: 8.6 (High)
  • Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

Mitigation and recommended actions

  • Immediate: Upgrade Kestra to version 2.0.0 or later, which patches the flaw.
  • If immediate patching is not possible: restrict network egress from the Kestra server/host to prevent outbound requests to internal address ranges and cloud metadata endpoints (e.g., via egress firewall rules or a metadata service proxy), and restrict who can create or import Flows until the upgrade is applied.

How IONIX identifies potentially affected assets

IONIX matches the following signals against data already collected when it crawled the asset; identifying the technology sends no request beyond that crawl.

  • Page title: Kestra
  • Raw response body: Kestra appearing near io.kestra.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge