A bug in Apache Airflow's XCom PATCH endpoint PATCH /api/v2/xcomEntries/{key} allowed an authenticated UI/API user with XCom write permission on a Dag to set XCom entries under reserved key names (e.g. returnvalue) that the matching POST endpoint already validated against FORBIDDENXCOMKEYS. The endpoint also accepted serialized payload shapes the triggerer's deserializer treats as code; combined, this allowed RCE on the triggerer when the affected task next deferred. Affects deployments where untrusted users have XCom write permission on Dags that defer to the triggerer. This is a fix-bypass of CVE-2026-33858: PR #64148 added the FORBIDDENXCOMKEYS validator only on the POST/set path; the PATCH path was not covered. Users who already upgraded for CVE-2026-33858 should additionally upgrade to apache-airflow 3.2.2 or later to cover the PATCH-path bypass.

A bug in Apache Airflow's bulk Task Instances API (PATCH/DELETE /api/v2/dags/{dagid}/dagRuns/{dagrunid}/taskInstances) evaluated authorization against the dagid resolved from the URL path while operating on the dagid / dagrunid extracted from request-body entity fields. An authenticated UI/API user with edit permission on one Dag could mutate Task Instance state in any other Dag by keeping the authorized Dag's ID in the URL path and naming the target Dag's IDs in the request body entities. Affects deployments that rely on per-Dag edit-scope to keep Task Instance state isolated between teams. Users are advised to upgrade to apache-airflow 3.2.2 or later.

The partitioneddagruns endpoints in the Airflow UI enforced only asset-level access control, not per-Dag authorization. An authenticated UI/API user with global Asset:read permission could enumerate partition run state, schedule configuration, and asset wiring for Dags they were not authorized to read. Affects deployments that rely on per-Dag read scoping while granting users broader Asset access. Users are advised to upgrade to apache-airflow 3.2.2 or later.