Fix CVE-2023-30861 in Flask HIGH

Fix CVE-2023-30861 (secure cookie bypass) in Flask for PyPI. Paste your requirements.txt into PackageFix and get a patched version back — no CLI, no signup.

⚠ Vulnerability

CVE-2023-30861 — secure cookie bypass in Flask. Update to 3.0.3 or later.

Vulnerable Version — requirements.txt

Flask==2.0.0

Fixed Version — requirements.txt

Flask==3.0.3
✓ Fix

Update to 3.0.3 and run pip install -r requirements.txt to apply the fix.

Scan your dependencies now — paste your manifest, get a fixed version back in seconds.

Open PackageFix →

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Frequently Asked Questions

What is CVE-2023-30861?
CVE-2023-30861 is a vulnerability in Flask that allows secure cookie bypass. Update to version 3.0.3 or later to fix it.
Is CVE-2023-30861 on the CISA KEV catalog?
Check the live CISA KEV catalog at packagefix.dev — the catalog updates daily and PackageFix always reflects the current status.
How do I fix CVE-2023-30861 in Flask?
Update Flask to version 3.0.3 or later in your requirements.txt. Run pip install -r requirements.txt after updating.
Does CVE-2023-30861 affect all versions of Flask?
Check the OSV advisory for the exact affected version range. PackageFix shows the minimum safe version for your installed version.