Description
Apache Airflow's Task SDK rebuilt a `Callback` object from serialized data by re-running its constructor, which imports the module named by the stored callback path. Because `SyncCallback` is itself an Airflow class it passes the default `allowed_deserialization_classes` allow-list, so tightening that setting does not help. A Dag author — who controls a task instance's `next_kwargs` through the task execution API — can therefore cause an arbitrary module to be imported inside the scheduler process, when the scheduler's `awaiting_input` timeout sweep deserializes that value. No non-default configuration is required; the sweep runs unconditionally. Versions before 3.3.0 are not affected: the class existed, but the scheduler sweep that reaches it did not. This is a separate code path from CVE-2026-58076 and CVE-2026-67260, which cover different gadgets reaching deserialization — applying either of those fixes does not address this one. Users are advised to upgrade to apache-airflow 3.3.1 or later.
Affected products
apache: airflow
References4
- lists.apache.org/thread/o00ww4n69qojvsckb464dtwd2nhzy6t0 Mailing ListVendor Advisory
- github.com/apache/airflow/pull/70704 Issue TrackingPatch
- www.cve.org/CVERecord?id=CVE-2026-58076 Not Applicable
- www.cve.org/CVERecord?id=CVE-2026-67260 Not Applicable
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 50 · as of 12 November 2026
- CWE
- CWE-502
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