---
id: "CVE-2026-82337"
page: "https://infrastack.ai/live/CVE-2026-82337"
kind: "vulnerability"
aliases: ["CVE-2026-82337"]
title: "Apache Airflow: Dag authors can construct allow-listed classes in scheduler"
severity: "high"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["apache-airflow", "api-server", "runtime", "scheduler", "self-hosted"]
not_affected_if: ["no-deadline-alerts", "restricted-dag-authors"]
published_at: "2026-11-09T10:17:11+00:00"
first_seen_at: "2026-11-09T10:25:49+00:00"
updated_at: "2026-11-09T10:26:40+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-82337", "first_seen_at": "2026-11-09T10:25:49+00:00"}]
exploit_sources: []
---

# Apache Airflow: Dag authors can construct allow-listed classes in scheduler

Link for people: https://infrastack.ai/live/CVE-2026-82337 (this .md is for agents)

Apache Airflow rebuilds deadline alert fields through generic deserialization, which imports and instantiates classes named in a serialized Dag. A Dag author can construct classes on Airflow's deserialization allow list inside the scheduler and API server, using arguments they control.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check whether Dags use deadline alerts (`DeadlineAlert` or `deadline_alerts` in Dag code).
- Check the installed version with `airflow version`; versions below `3.4.0` are in scope per the advisory.

## Fix

- apache-airflow: upgrade to `3.4.0` or later.

## Timeline

- 2026-11-09T10:25:49+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-82337

## From the sources

Apache Airflow rebuilt deadline alert fields through generic deserialization, which imports and instantiates the class named in the serialized Dag, in the scheduler and API server. A Dag author could cause classes within Airflow's deserialization allow list to be constructed in those processes with arguments they control. Deployments whose Dags use deadline alerts are affected.

This is an incomplete fix of CVE-2026-45360, which only hardened the `reference` field; deployments that applied that fix remain affected through the `callback` and `interval` fields.

Users of apache-airflow are recommended to upgrade to 3.4.0 or later.

---

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