Cyber Resilience

CVE-2026-40690

Apache Airflow ≤ 3.2.1

Published
24 April 2026
Modified
27 April 2026
Patch / advisory
View advisory
CVSS Score v3.1 4.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS Score 0.0035 28th percentile
Risk Priority 36 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-40690 is a medium-severity Insufficient Granularity of Access Control (CWE-1220) vulnerability in Apache Airflow. Its CVSS base score is 4.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Services File Permissions Weakness (T1574.010); ranked at the 28th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-3 (Access Enforcement) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

The asset dependency graph did not restrict nodes by the viewer's DAG read permissions: a user with read access to at least one DAG could browse the asset graph for any other asset in the deployment and learn the existence…

more

and names of DAGs and assets outside their authorized scope. Users are recommended to upgrade to version 3.2.1, which fixes this issue.

CWE(s)
CWE-1220

Related Threats

MITRE ATT&CK Enterprise Techniques

T1574.010 Services File Permissions Weakness Stealth
Adversaries may execute their own malicious payloads by hijacking the binaries used by services.
attack.mitre.org →
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
attack.mitre.org →
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
attack.mitre.org →
T1556 Modify Authentication Process Defense Impairment
Adversaries may modify authentication mechanisms and processes to access user credentials or enable otherwise unwarranted access to accounts.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-38743Same product: Apache Airflow
CVE-2026-30911Same product: Apache Airflow
CVE-2024-27906Same product: Apache Airflow
CVE-2026-41014Same product: Apache Airflow
CVE-2023-50944Same product: Apache Airflow
CVE-2021-38540Same product: Apache Airflow
CVE-2020-13927Same product: Apache Airflow
CVE-2026-22922Same product: Apache Airflow
CVE-2023-25754Same product: Apache Airflow
CVE-2024-26280Same product: Apache Airflow

Affected Assets

apache
airflow
≤ 3.2.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V16.4.2
  • V8.4.2
  • V11.7.1
  • V13.2.4

Mitigating Controls (NIST 800-53 r5) AI

AC-6 Least Privilege good match

Least privilege explicitly demands that only the minimum necessary accesses are granted, eliminating the broad permissions that define this weakness.

AC-24 Access Control Decisions good match

AC-24 requires access decisions to be applied precisely and unambiguously to every request, structurally blocking insufficiently granular policies.

AC-3 Access Enforcement good match

AC-3 requires enforcement of authorizations according to policy, directly compelling sufficiently granular rules so broad allowances cannot be introduced.

AC-4 Information Flow Enforcement partial match

AC-4 enforces approved information flows with explicit source/destination rules, preventing overly coarse access policies from being deployed.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.IR-01 mostly match
prevents

PR.IR-01's segmentation + zero-trust rules directly enforce minimum-necessary access at network boundaries, removing most instances of overly broad policy; CWE-1220 can still exist in application-layer or intra-segment controls that this single outcome does not address.

PR.PS-06 partial match
prevents

PR.PS-06's general SDLC practices can surface granularity issues during design/review (partial prevention) but do not specifically target access-control policy breadth, so they remove only part of CWE-1220's risk.

DE.AE-06 none match
degrades

CWE-1220 permits unauthorized access to sensitive assets but neither prevents nor impairs the delivery of adverse-event information to authorized recipients.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.3 Information access restriction mostly match
degrades

Directly requires information-access restriction at the level of individual assets and operations, addressing the granularity gap.

A.5.15 Access control partial match
prevents

Establishes the overarching access-control policy whose granularity directly determines whether the weakness exists.

A.5.18 Access rights partial match
prevents

Defines the assignment and review of access rights; insufficient granularity in those rights is the root of CWE-1220.

A.8.2 Privileged access rights partial match
prevents

Specifies management of privileged access rights, where overly broad privileges are a common manifestation of the weakness.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Windows Server 2016 (1 rule)
  • V-225025 Local accounts with blank passwords must be restricted to prevent access from the network. prevents CWE-1220

References