Apache Airflow Backfill API parser discrepancy permits cross-DAG authorization bypass

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS

• CVE-2026-68968: 0.42% estimated exploitation activity in the next 30 days; percentile 36.01 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Apache Airflow's Backfill API authorized a request against a Dag id supplied by the caller whenever the backfillid path segment failed to parse. The authorization dependency parsed it with int() while the route handler parsed it as pydantic's NonNegativeInt, which accepts values int() rejects (1.0 coerces to 1); FastAPI resolves dependencies before endpoint validation, so the two acted on different Dags. An authenticated user holding edit permission on any single Dag could therefore read, pause and cancel backfills belonging to any other Dag, including moving another Dag's queued runs to failed. No non-default configuration is required and backfill ids are sequential, so finding a target is trivial. Users are advised to upgrade to apache-airflow 3.3.1 or later, which parses the backfill id with the same type the routes declare.

Published by the source

12 Aug 2026, 18:31 UTC

Last modified by the source

2 Oct 2026, 23:14 UTC

Source last checked

26 Oct 2026, 13:54 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-j4jc-cq9h-xrhr

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# Patch Next advisory brief: CVE-2026-68968

Advisory: Apache Airflow Backfill API parser discrepancy permits cross-DAG authorization bypass
IDs: CVE-2026-68968, GHSA-j4jc-cq9h-xrhr
Record: https://patchnext.com/advisories/cve-2026-68968 (revision 1, source checked 26 Oct 2026, 13:54 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: apache-airflow 3.3.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI apache-airflow: affected < 3.3.1; fixed in 3.3.1

## Suggested inspection (read-only)
- `python -m pip show apache-airflow`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on apache-airflow.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-j4jc-cq9h-xrhr (GitHub-reviewed advisory GHSA-j4jc-cq9h-xrhr lists affected ranges: PyPI apache-airflow >=0 <3.3.1)

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