CVE-2026-49869
Kestra: Unauthenticated Remote Code Execution via Authentication Bypass in `AuthenticationFilter`
- Critical 10.0
- Exploited: added to CISA KEV 2 Sep 2026
Description
Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, AuthenticationFilter in Kestra OSS uses request.getPath().endsWith("/configs") to whitelist the public configuration endpoint from Basic Auth. Because the check is a suffix match rather than an exact path match, any API path whose last segment is configs bypasses authentication entirely. An unauthenticated remote attacker can exploit this to create and execute arbitrary workflows without credentials. Because Kestra ships with script execution plugins (plugin-script-shell, plugin-script-python, etc.) enabled by default, this directly results in unauthenticated Remote Code Execution as root inside the Kestra worker container. This vulnerability is fixed in 1.0.45 and 1.3.21.
Key facts
- Published
- 26 Jun 2026
- Last changed
- 3 Sep 2026
- Assigned by
- GitHub_M
- KEV added
- 2 Sep 2026
- KEV fix due
- 5 Sep 2026
- EPSS
- 2.095% likely to be exploited in the next 30 days, higher than 81.965% of CVEs (scores for 15 Nov 2026)
- SSVC (CISA)
- Exploitation: active; Automatable: yes; Technical impact: total
Severity scores
Each score is shown as its source gave it. They are not averaged or merged.
- 10.0CVSS 3.1, Criticalfrom the CNA (GitHub_M)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
What to do
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.CISA KEV required action
Historical context and remediation
This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.
No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.
Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.
Affected products
| Vendor | Product | Versions |
|---|---|---|
| kestra-io | kestra |
|
Timeline
- 26 Jun 2026 Published
- 2 Sep 2026 CVE-2026-49869 added to CISA KEV
- 2 Sep 2026 Added to the CISA KEV catalogue
Weakness
Practice this bug class
HackZoneLabs has a hands-on lab on OS command injection (CWE-78).