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🐍 PyPI

CVE-2022-42731

HIGH

django-mfa2 vulnerable to MFA Replay attack

Also known asGHSA-vw39-2wj9-4q86PYSEC-2022-303
Published
Oct 11, 2022
Updated
Apr 10, 2026
Affected
2 pkgs
Patched
2 / 2
Exploits
1 known

EPSS Exploitation Probability

via FIRST.org ↗
1.0%probability of exploitation in next 30 days
Lower Risk58th percentile+0.58%
0.00%0.50%1.00%1.51%0.2%1.0%Dec 25Apr 26Jun 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

2 pkgs affected
🐍django-mfa2🐍django-mfa2

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

mfa/FIDO2.py in django-mfa2 before 2.5.1 and 2.6.x before 2.6.1 allows a replay attack that could be used to register another device for a user. The device registration challenge is not invalidated after usage.

Affected Packages

2 total 2 fixed
EcosystemPackageVulnerable rangeFix
🐍PyPIdjango-mfa2all versions2.5.1
🐍PyPIdjango-mfa22.6.0&&< 2.6.12.6.1
Exploits & PoCs
1

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for django-mfa2. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update django-mfa2 to 2.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-42731 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether CVE-2022-42731 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2022-42731. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

mfa/FIDO2.py in django-mfa2 before 2.5.1 and 2.6.x before 2.6.1 allows a replay attack that could be used to register another device for a user. The device registration challenge is not invalidated after usage.
O3 Security · Impact-Aware SCA

Is CVE-2022-42731 in your dependencies?

O3 detects CVE-2022-42731 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.