AVID-2026-R0815

Description

Regular Expression Denial of Service in flask-restx (CVE-2021-32838)

Details

Flask-RESTX (pypi package flask-restx) is a community driven fork of Flask-RESTPlus. Flask-RESTX before version 0.5.1 is vulnerable to ReDoS (Regular Expression Denial of Service) in email_regex. This is fixed in version 0.5.1.

Reason for inclusion in AVID: CVE-2021-32838 describes a Regular Expression Denial of Service in flask-restx, a Python web API framework widely used to build and serve AI/ML model endpoints. While the vulnerability targets a general web framework, such frameworks are commonly part of AI model serving stacks and deployment pipelines. The issue is a software vulnerability with measurable impact (DoS) and has clear versions affected and a fixed version, providing sufficient evidence for curation as a software supply-chain vulnerability affecting AI systems.

References

• NVD entry
• https://github.com/advisories/GHSA-3q6g-vf58-7m4g
• https://github.com/python-restx/flask-restx/issues/372
• https://github.com/python-restx/flask-restx/commit/bab31e085f355dd73858fd3715f7ed71849656da
• https://github.com/python-restx/flask-restx/blob/fd99fe11a88531f5f3441a278f7020589f9d2cc0/flask_restx/inputs.py#L51
• https://pypi.org/project/flask-restx/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5UCTFVDU3677B5OBGK4EF5NMUPJLL6SQ/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QUD6SWZLX52AAZUHDETJ2CDMQGEPGFL3/

Affected or Relevant Artifacts

• Developer: python-restx
• Deployer: python-restx
• Artifact Details:

Impact

AVID Taxonomy Categorization

• Risk domains: Security
• SEP subcategories: S0100: Software Vulnerability
• Lifecycle stages: L06: Deployment

CVSS

CWE

Other information

• Report Type: Advisory
• Credits:
• Date Reported: 2021-09-20
• Version: 0.3.3
• AVID Entry