CVE-2022-36071 — v2
HIGHCVE-2022-36071 is a high-severity (CVSS 8.3) Improper Authentication vulnerability in github.com/drakkan/sftpgo/v2. 1 public exploit reference exists, so weaponization risk is real. A fix is available for github.com/drakkan/sftpgo/v2 — see the affected versions and patch details below.
Recovery codes abuse in SFTPGo
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.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2022-36071.
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-2022-36071 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 376,715 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/drakkan/sftpgo/v2Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
SFTPGo is configurable SFTP server with optional HTTP/S, FTP/S and WebDAV support. SFTPGo WebAdmin and WebClient support login using TOTP (Time-based One Time Passwords) as a secondary authentication factor. Because TOTPs are often configured on mobile devices that can be lost, stolen or damaged, SFTPGo also supports recovery codes. These are a set of one time use codes that can be used instead of the TOTP. In SFTPGo versions from version 2.2.0 to 2.3.3 recovery codes can be generated before enabling two-factor authentication. An attacker who knows the user's password could potentially generate some recovery codes and then bypass two-factor authentication after it is enabled on the account at a later time. This issue has been fixed in version 2.3.4. Recovery codes can now only be generated after enabling two-factor authentication and are deleted after disabling it.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/drakkan/sftpgo/v2 | ≥ 2.2.0&&< 2.3.4 | 2.3.4go get github.com/drakkan/sftpgo/v2@v2.3.4 |
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 dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/drakkan/sftpgo/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/drakkan/sftpgo/v2 to 2.3.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-36071 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-2022-36071 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2022-36071. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2022-36071 in your dependencies?
O3 Security finds CVE-2022-36071 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.