How severe is CVE-2021-26697?

CVE-2021-26697 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-26697 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26697?

CVE-2021-26697 affects Apache Airflow. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26697?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-26697 published?

CVE-2021-26697 was published on 2021-02-17 and last updated on 2026-06-17.

CVE-2021-26697

CVE-2021-26697 is a medium-severity vulnerability in Apache Airflow with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-306.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 5% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Apache Airflow
Published: 2021-02-17
Last modified: 2026-06-17

Description

The lineage endpoint of the deprecated Experimental API was not protected by authentication in Airflow 2.0.0. This allowed unauthenticated users to hit that endpoint. This is low-severity issue as the attacker needs to be aware of certain parameters to pass to that endpoint and even after can just get some metadata about a DAG and a Task. This issue affects Apache Airflow 2.0.0.

Frequently asked questions

What is CVE-2021-26697?: The lineage endpoint of the deprecated Experimental API was not protected by authentication in Airflow 2.0.0. This allowed unauthenticated users to hit that endpoint. This is low-severity issue as the attacker needs to be aware of certain parameters to pass to that endpoint and even after can just get some metadata about a DAG and a Task. This issue affects Apache Airflow 2.0.0.
How severe is CVE-2021-26697?: CVE-2021-26697 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-26697 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26697?: CVE-2021-26697 affects Apache Airflow. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26697?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-26697 published?: CVE-2021-26697 was published on 2021-02-17 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:airflow:2.0.0:*:*:*:*:*:*:*

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