How severe is CVE-2021-29621?

CVE-2021-29621 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-2021-29621 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29621?

CVE-2021-29621 primarily affects Dpgaspar Flask-appbuilder. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-29621?

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

When was CVE-2021-29621 published?

CVE-2021-29621 was published on 2021-06-07 and last updated on 2026-06-17.

CVE-2021-29621

CVE-2021-29621 is a medium-severity vulnerability in Dpgaspar Flask-appbuilder 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Dpgaspar Flask-appbuilder
Published: 2021-06-07
Last modified: 2026-06-17

Description

Flask-AppBuilder is a development framework, built on top of Flask. User enumeration in database authentication in Flask-AppBuilder <= 3.2.3. Allows for a non authenticated user to enumerate existing accounts by timing the response time from the server when you are logging in. Upgrade to version 3.3.0 or higher to resolve.

Frequently asked questions

What is CVE-2021-29621?: Flask-AppBuilder is a development framework, built on top of Flask. User enumeration in database authentication in Flask-AppBuilder <= 3.2.3. Allows for a non authenticated user to enumerate existing accounts by timing the response time from the server when you are logging in. Upgrade to version 3.3.0 or higher to resolve.
How severe is CVE-2021-29621?: CVE-2021-29621 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-2021-29621 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29621?: CVE-2021-29621 primarily affects Dpgaspar Flask-appbuilder. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-29621?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-29621 published?: CVE-2021-29621 was published on 2021-06-07 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:dpgaspar:flask-appbuilder:*:*:*:*:*:*:*:*
cpe:2.3:a:apache:airflow:1.10.0:*:*:*:*:*:*:*

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