PYSEC-2026-3708
Vulnerability from pysec - Published: 2026-08-12 16:17 - Updated: 2026-08-19 13:09Apache 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.
| Name | purl | apache-airflow | pkg:pypi/apache-airflow |
|---|
{
"affected": [
{
"ecosystem_specific": {},
"package": {
"ecosystem": "PyPI",
"name": "apache-airflow",
"purl": "pkg:pypi/apache-airflow"
},
"ranges": [
{
"events": [
{
"introduced": "3.3.0"
},
{
"fixed": "3.3.1"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"3.3.0",
"3.3.1rc1",
"3.3.1rc2"
]
}
],
"aliases": [
"CVE-2026-67587"
],
"details": "Apache Airflow\u0027s 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 \u2014 who controls a task instance\u0027s `next_kwargs` through the task execution API \u2014 can therefore cause an arbitrary module to be imported inside the scheduler process, when the scheduler\u0027s `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 \u2014 applying either of those fixes does not address this one. Users are advised to upgrade to apache-airflow 3.3.1 or later.",
"id": "PYSEC-2026-3708",
"modified": "2026-08-19T13:09:03.140566Z",
"published": "2026-08-12T16:17:15.090Z",
"references": [
{
"type": "WEB",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-58076"
},
{
"type": "WEB",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-67260"
},
{
"type": "ADVISORY",
"url": "https://lists.apache.org/thread/o00ww4n69qojvsckb464dtwd2nhzy6t0"
},
{
"type": "FIX",
"url": "https://github.com/apache/airflow/pull/70704"
}
],
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.