CVE-2021-29621

Observable Response Discrepancy in Flask-AppBuilder

MEDIUM
5.3
CVSS Score
Published: June 7, 2021 at 07:00 PM UTC
Updated: June 17, 2026 at 03:48 AM UTC
2 products affected across 2 vendorsAirflowFlask-AppBuilder

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Severity
MEDIUM5.3
Exploit prediction
EPSS 3%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 3.2.3v < 3.3.0
Affected range stops below 3.3.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

5.3MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-203

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