{"id":"CVE-2026-111421","published":"2026-11-09T10:17:03.773","lastModified":"2026-11-10T21:12:56.800","description":"Apache Airflow's Task Execution API stored XCom values written by a task without the reserved-key check applied elsewhere, so a Dag author's task could write an XCom that, when a user later viewed it through the API with deserialization enabled, made the API server instantiate classes from the `airflow.*` namespace with arguments the Dag author chose. This is an incomplete fix for CVE-2026-59242: users who applied that fix in apache-airflow 3.3.1 remain affected through this route and should upgrade to apache-airflow 3.4.0 or later.","cvssScore":8.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwes":["CWE-502"],"vendors":[],"products":[],"references":[{"url":"https://github.com/apache/airflow/pull/72718","tags":[]},{"url":"https://github.com/apache/airflow/pull/74829","tags":[]},{"url":"https://lists.apache.org/thread.html/pwdwx354tv0x3m8wzfhh59r6wyztj2lk","tags":[]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-59242","tags":[]}],"exploitRefs":[{"url":"https://github.com/apache/airflow/pull/72718","tags":[]},{"url":"https://github.com/apache/airflow/pull/74829","tags":[]}],"hasPoc":true,"ai":{"summary":"Apache Airflow's Task Execution API failed to enforce the reserved-key check on XCom values written by tasks, allowing malicious DAG authors to inject deserialized objects via crafted XComs. When users viewed these XComs through the API with deserialization enabled, the Airflow server instantiated arbitrary classes from the airflow.* namespace using attacker-controlled arguments, enabling remote code execution.","exploitability":"Exploitation requires low-privilege access (PR:L) as a DAG author who can write tasks that store XComs; no user interaction or complex conditions are needed beyond enabling deserialization in the API.","blast_radius":"Successful exploitation grants full compromise of the Airflow API server (CIA high impact), potentially affecting all downstream systems accessible to the Airflow service account.","remediation":"Upgrade to apache-airflow 3.4.0 or later, which fully addresses this incomplete fix for CVE-2026-59242.","detection":"No reliable host or network indicator is derivable from the published description.","tags":["deserialization","rce","airflow","xcom","insecure-deserialization"],"model":"garnet-coder","analyzedAt":"2026-11-10T09:46:57.667Z"}}