GHSA-HF33-Q6CF-C66F
Vulnerability from github – Published: 2026-09-21 21:47 – Updated: 2026-09-21 21:47Summary
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": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/lucasdillmann/nginx-ignition"
},
"ranges": [
{
"events": [
{
"introduced": "0.0.0-20260217145239-1cbfae0296f1"
},
{
"fixed": "0.0.0-20260328015550-8d35e1eb5dd6"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-61630"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": true,
"github_reviewed_at": "2026-09-21T21:47:40Z",
"nvd_published_at": "2026-09-21T15:17:30Z",
"severity": "MODERATE"
},
"details": "### Summary\nAny user that has enabled the OTP 2FA can have their TOTP reused during the standard 30 second validity window.\n\n### Details\nThe https://github.com/pquerna/otp package [doesn\u0027t include](https://github.com/pquerna/otp/issues/61) 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\u0027t be reused.\n\nSection 6.5.1 within the [Authentication](https://github.com/OWASP/ASVS/blob/master/5.0/en/0x15-V6-Authentication.md) section of the OWASP ASVS recommends multiple checks, some of which involving TOTPs:\n\n\u003e Verify that lookup secrets, out-of-band authentication requests or codes, and time-based one-time passwords (TOTPs) are only successfully usable once.\n\nThe OWASP WSTG also references this as one of their [checks](https://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/04-Authentication_Testing/11-Testing_Multi-Factor_Authentication) to look for:\n\n\u003e Can the OTPs be used more than once?\n\n### PoC\n\nhttps://github.com/user-attachments/assets/86a43374-39bf-4d61-8f6d-5cc440c99a1e\n\n### Impact\nAny user who uses 2FA could be impacted if their traffic is able to be captured, they\u0027re phished/social engineered, or other methods of attack. This disrupts one layer of the defense-in-depth model surrounding 2FA.\n\n### Similar CVEs\n- [CVE-2025-6014](https://nvd.nist.gov/vuln/detail/CVE-2025-6014)\n- [CVE-2025-55003](https://nvd.nist.gov/vuln/detail/CVE-2025-55003)\n- [CVE-2026-33473](https://github.com/go-vikunja/vikunja/security/advisories/GHSA-p747-qc5p-773r)\n\n### Remediation\nStore 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.",
"id": "GHSA-hf33-q6cf-c66f",
"modified": "2026-09-21T21:47:40Z",
"published": "2026-09-21T21:47:40Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/lucasdillmann/nginx-ignition/security/advisories/GHSA-hf33-q6cf-c66f"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-61630"
},
{
"type": "WEB",
"url": "https://github.com/pquerna/otp/issues/61"
},
{
"type": "WEB",
"url": "https://github.com/lucasdillmann/nginx-ignition/pull/104"
},
{
"type": "WEB",
"url": "https://github.com/lucasdillmann/nginx-ignition/commit/1cbfae0296f1b186158f5a294ec484060e00102e"
},
{
"type": "WEB",
"url": "https://github.com/lucasdillmann/nginx-ignition/commit/8d35e1eb5dd6a40fef94a45511fe08b0603af107"
},
{
"type": "PACKAGE",
"url": "https://github.com/lucasdillmann/nginx-ignition"
},
{
"type": "WEB",
"url": "https://github.com/lucasdillmann/nginx-ignition/releases/tag/2.35.1"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "nginx ignition has TOTP Reuse During Validity Window"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.