CyberSecBulletin
CVE-2026-96285NVD status: Awaiting Analysis

Apache Airflow: Deserialization of Untrusted Data

CVE-2026-96285 is a high-severity deserialization of untrusted data vulnerability in Apache Airflow from Apache, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 3.4.0 as the first without the flaw, so updating Apache Airflow to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.59% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache Airflow to 3.4.0 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache Airflow3.3.0 up to, but not including, 3.4.03.4.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

Apache Airflow 3.3.1 shipped a fix for CVE-2026-67260 that checks the scheduler's decoded `next_kwargs` value is a dictionary, but performs that check only after deserializing the whole stored payload. Deserialization reconstructs nested objects of classes permitted by the deserialization allow-list — which by default includes Airflow's own classes — and runs their constructors inside the scheduler process before the check can reject the value. A Dag author, who controls a task's `next_kwargs` through the task execution API, can therefore still trigger constructor execution in the scheduler when the `awaiting_input` timeout sweep processes the task, and in the API server when the task instance is served to a worker using an older Execution API version; no non-default configuration is required. Versions before 3.3.0 are not affected. This is an incomplete fix for CVE-2026-67260: deployments that upgraded to 3.3.1 for that issue must also upgrade to apache-airflow 3.4.0 or later.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Apache Airflow

All Apache Airflow vulnerabilities

Recent Deserialization of Untrusted Data vulnerabilities

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