CVE-2026-30911 Overview
Apache Airflow versions 3.1.0 through 3.1.7 contain a missing authorization vulnerability (CWE-862) in the Execution API's Human-in-the-Loop (HITL) endpoints. This flaw allows any authenticated task instance to read, approve, or reject HITL workflows belonging to any other task instance, effectively bypassing intended access controls and enabling unauthorized cross-task operations.
Critical Impact
Authenticated attackers can manipulate workflow approvals across task boundaries, potentially compromising data pipeline integrity, approving malicious operations, or disrupting critical business workflows.
Affected Products
- Apache Airflow versions 3.1.0 through 3.1.7
- Apache Airflow installations utilizing HITL workflow features
- Environments with multi-tenant task instances sharing Airflow infrastructure
Discovery Timeline
- 2026-03-17 - CVE-2026-30911 published to NVD
- 2026-03-17 - Last updated in NVD database
Technical Details for CVE-2026-30911
Vulnerability Analysis
This vulnerability represents a classic Missing Authorization flaw where the Execution API fails to properly validate that an authenticated task instance has the appropriate permissions to interact with HITL workflows owned by other task instances. The HITL feature, designed to require human approval for sensitive workflow steps, becomes exploitable when authorization checks are absent or improperly implemented.
The vulnerability enables horizontal privilege escalation where any authenticated task can access, approve, or reject workflows it should not have visibility into. This breaks the fundamental security boundary expected in multi-tenant or multi-workflow Airflow deployments where task isolation is assumed.
Root Cause
The root cause is missing authorization checks in the HITL endpoint handlers within the Execution API. When processing requests to read, approve, or reject HITL workflows, the API authenticates the requesting task instance but fails to verify whether that task instance owns or has explicit permissions to interact with the targeted workflow. This allows any valid authenticated session to perform operations on arbitrary HITL workflows by manipulating request parameters.
Attack Vector
The attack is network-accessible and requires low-privilege authentication. An attacker with access to any authenticated task instance within the Airflow environment can craft API requests targeting HITL endpoints for workflows belonging to other task instances. The attack does not require user interaction and can be executed programmatically.
The exploitation process involves:
- Authenticating as any valid task instance in the Airflow environment
- Enumerating or guessing HITL workflow identifiers belonging to other task instances
- Sending API requests to the HITL endpoints (read, approve, or reject) with the target workflow ID
- Successfully manipulating workflows without proper ownership verification
No verified proof-of-concept code is publicly available. For technical implementation details, refer to the GitHub Pull Request which contains the security fix addressing this authorization gap.
Detection Methods for CVE-2026-30911
Indicators of Compromise
- HITL workflow approvals or rejections from task instances that do not own those workflows
- Unusual patterns in Execution API access logs showing cross-task workflow operations
- Unexpected workflow state changes without corresponding legitimate human approvals
- API requests to HITL endpoints with workflow IDs not associated with the requesting task
Detection Strategies
- Implement logging correlation between task instance identity and HITL workflow ownership
- Monitor for anomalous spikes in HITL endpoint access across different task contexts
- Deploy API gateway rules to flag requests where task ID and workflow ownership mismatch
- Review Airflow audit logs for unauthorized workflow state transitions
Monitoring Recommendations
- Enable verbose logging on all Execution API HITL endpoints
- Configure alerts for HITL operations performed outside of expected business hours or by unexpected tasks
- Implement workflow ownership validation in monitoring dashboards
- Establish baseline behavior patterns for HITL approval workflows to detect deviations
How to Mitigate CVE-2026-30911
Immediate Actions Required
- Upgrade Apache Airflow to version 3.1.8 or later immediately
- Audit recent HITL workflow approvals and rejections for unauthorized activity
- Review Execution API access logs for suspicious cross-task operations
- Implement network segmentation to limit task instance API access if upgrade cannot be performed immediately
Patch Information
Apache has released version 3.1.8 which resolves this authorization vulnerability. The fix adds proper ownership verification to HITL endpoint handlers, ensuring task instances can only interact with workflows they legitimately own.
For detailed patch information, see the GitHub Pull Request #62886 and the Apache Mailing List Thread.
Workarounds
- Disable HITL functionality if not operationally required until patch can be applied
- Implement network-level access controls to restrict Execution API access to trusted task instances only
- Deploy an API gateway or reverse proxy with custom authorization rules validating workflow ownership
- Enable strict authentication and consider additional authorization layers at the infrastructure level
# Example: Restrict Execution API access at network level (iptables)
# Allow only trusted task instance IPs to access HITL endpoints
iptables -A INPUT -p tcp --dport 8080 -s trusted_task_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 8080 -j DROP
# Example: Disable HITL feature in Airflow configuration if not needed
# In airflow.cfg
# [core]
# enable_hitl = False
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
