CVE-2026-61630
nginx ignition has TOTP Reuse During Validity Window
nginx ignition is a user interface for the nginx web server. In versions 2.33.0 through 2.35.0, any user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window. Version 2.35.1 patches the issue.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- High
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
nginx ignition has TOTP Reuse During Validity Window
nginx ignition is a user interface for the nginx web server. In versions 2.33.0 through 2.35.0, any user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window. Version 2.35.1 patches the issue.
- Record
CVE-2026-61630- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
EUVDEUVD-2026-83922
nginx ignition is a user interface for the nginx web server. In versions 2.33.0 through 2.35.0, any user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window. Version 2.35.1 patches the issue.
- Record
EUVD-2026-83922- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-hf33-q6cf-c66f
nginx ignition has TOTP Reuse During Validity Window
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.
- Record
GHSA-hf33-q6cf-c66f- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
NVD
nginx ignition is a user interface for the nginx web server. In versions 2.33.0 through 2.35.0, any user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window. Version 2.35.1 patches the issue.
- Record
CVE-2026-61630- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
OSV
nginx ignition has TOTP Reuse During Validity Window
nginx ignition is a user interface for the nginx web server. In versions 2.33.0 through 2.35.0, any user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window. Version 2.35.1 patches the issue.
- Record
CVE-2026-61630- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
OSVGHSA-hf33-q6cf-c66f
nginx ignition has TOTP Reuse During Validity Window
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.
- Record
GHSA-hf33-q6cf-c66f- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-61630
nginx ignition is a user interface for the nginx web server. In versions 2.33.0 through 2.35.0, any user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window. Version 2.35.1 patches the issue.
- Record
UBUNTU-CVE-2026-61630- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVGO-2026-6537 No score
nginx ignition has TOTP Reuse During Validity Window in github.com/lucasdillmann/nginx-ignition
nginx ignition has TOTP Reuse During Validity Window in github.com/lucasdillmann/nginx-ignition
- Record
GO-2026-6537- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/lucasdillmann/nginx-ignitionGo |
0.0.0-20260217145239-1cbfae0296f1 up to 0.0.0-20260328015550-8d35e1eb5dd6 | 0.0.0-20260328015550-8d35e1eb5dd6 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-61630 is a medium vulnerability (CVSS 4.2) in Lucasdillmann Nginx-ignition, published September 21, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.38%, the 32nd percentile. Fixed in github.com/lucasdillmann/nginx-ignition 0.0.0-20260328015550-8d35e1eb5dd6.
References
github.com/lucasdillmann/nginx-ignition/security/advisories/GHSA-hf33-q6cf-c66f
nvd.nist.gov/vuln/detail/CVE-2026-61630