CVE-2023-0777 is a high-severity (CVSS 8.6) CWE-305 vulnerability in modoboa. 2 public exploit references exist, so weaponization risk is real. A fix is available for modoboa — see the affected versions and patch details below.
Authentication Bypass by Primary Weakness in modoboa/modoboa
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-0777.
EPSS Exploitation Probability
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.
How urgent is this, really
CVE-2023-0777 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
modoboaReal-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
Authentication Bypass by Primary Weakness in GitHub repository modoboa/modoboa prior to 2.0.4.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | modoboa | all versions | 2.0.4pip install --upgrade 'modoboa==2.0.4' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
modoboa 2.0.4 - Admin TakeOver
by 7h3h4ckv157 · Apr 6, 2023
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for modoboa, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update modoboa to 2.0.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-0777 is resolved across your whole dependency graph.
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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-0777 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-0777. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect CVE-2023-0777
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2023-0777 -u https://target- Template
- modoboa 2.0.4 - Admin TakeOver
- Severity
- critical
- Impact
- Unauthenticated attackers can exploit authentication bypass using default credentials to gain administrator access and completely compromise Modoboa email server installations.
- Remediation
- update to version 2.0.4
Template by ProjectDiscovery nuclei-templates (r3Y3r53), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2023-0777 in your dependencies?
O3 Security finds CVE-2023-0777 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.