nginx ignition has TOTP Reuse During Validity WindowGHSA-hf33-q6cf-c66f
MEDIUMFix: lucasdillmann/nginx-ignition#104GHSA-hf33-q6cf-c66f is a medium-severity (CVSS 4.2) Improper Authentication vulnerability in github.com/lucasdillmann/nginx-ignition. A fix is available for github.com/lucasdillmann/nginx-ignition — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-hf33-q6cf-c66f.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-hf33-q6cf-c66f by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
github.com/lucasdillmann/nginx-ignitionReal-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
Summary
Any user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window.
Details
The https://github.com/pquerna/otp package doesn't include checking for already used TOTPs within its the validity window. This requires each application that uses the package to implement their own method of tracking and verifying that codes can't be reused.
Section 6.5.1 within the Authentication section of the OWASP ASVS recommends multiple checks, some of which involving TOTPs:
Verify that lookup secrets, out-of-band authentication requests or codes, and time-based one-time passwords (TOTPs) are only successfully usable once.
The OWASP WSTG also references this as one of their checks to look for:
Can the OTPs be used more than once?
PoC
https://github.com/user-attachments/assets/86a43374-39bf-4d61-8f6d-5cc440c99a1e
Impact
Any user who uses 2FA could be impacted if their traffic is able to be captured, they're phished/social engineered, or other methods of attack. This disrupts one layer of the defense-in-depth model surrounding 2FA.
Similar CVEs
Remediation
Store a deny-list of TOTP codes for their validity windows and check submitted codes against it to ensure none are being reused. After their validity window has closed, the 2FA code can be removed from the list.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/lucasdillmann/nginx-ignition | ≥ 0.0.0-20260217145239-1cbfae0296f1&&< 0.0.0-20260328015550-8d35e1eb5dd6 | 0.0.0-20260328015550-8d35e1eb5dd6go get github.com/lucasdillmann/nginx-ignition@v0.0.0-20260328015550-8d35e1eb5dd6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/lucasdillmann/nginx-ignition, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/lucasdillmann/nginx-ignition to 0.0.0-20260328015550-8d35e1eb5dd6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hf33-q6cf-c66f is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is GHSA-hf33-q6cf-c66f in your dependencies?
Find it across Go, including transitive dependencies.