CVE-2026-43926
📛 CVE Title
FOSSBilling's password reset confirmation endpoint lacks rate limiting
Description
FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, the password reset confirmation endpoint `/client/reset-password-confirm/:hash` is handled by a non-API controller and is not covered by FOSSBilling's rate limiter, which only applies to `/api/*` routes. This allows an attacker to probe the endpoint for valid reset tokens without any per-IP request limiting, attempt counting, or lockout mechanism. The endpoint acts as an oracle, returning a distinguishable response for valid versus invalid tokens (HTTP 200 vs HTTP 302 redirect). An attacker can submit unlimited token guesses to the password reset confirmation endpoint with no throttling applied. However, practical exploitability is significantly mitigated by the current token generation, which uses `hash('sha256', random_bytes(32))`, providing 256 bits of entropy. Tokens also expire after 15 minutes and are deleted after successful use. The same architectural gap applies to other controller-served auth routes, including `/staff/email/:hash` (admin password reset confirmation) and `/client/confirm-email/:hash` (email confirmation). Version 0.8.0 fixes the issue. Some workarounds are available. Configure a reverse proxy (e.g., Nginx, Apache, Cloudflare) to apply per-IP rate limiting to the `/client/reset-password-confirm/*` and `/staff/email/*` paths and/or use a WAF rule to limit request rates to these endpoints.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- GitHub_M
- CVSS severity
- MEDIUM
- CVSS score
- 6.3 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N- Effective score
- 6.3 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-204,CWE-307 - Reserved
- 2026-05-04
- Published
- 2026-06-04 12:46 UTC
- Last updated
- 2026-06-04 14:37 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/43xxx/CVE-2026-43926.json
- Linked Threat
- CVE-2026-43926 — CVE-2026-43926
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-06-04 14:16:41 UTC
- NVD last modified
- 2026-07-22 20:10:00 UTC
- EPSS score
- 0.0022 (probability of exploitation in next 30 days)
- EPSS percentile
- 12.21% vs all CVEs — higher = more likely to be exploited, as of 2026-08-01
NVD / KEV / EPSS data refreshed 2026-08-01 16:41 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-34255 - Assigner
- GitHub_M
- Published
- Jun 4, 2026, 12:46:30 PM
- Updated
- Jun 4, 2026, 2:37:01 PM
- EUVD base score (CVSS 4.0)
-
6.3 / 10
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.2200
- Vendors
- fossbilling
- Products
-
FOSSBilling (< 0.8.0)
ENISA description: FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, the password reset confirmation endpoint `/client/reset-password-confirm/:hash` is handled by a non-API controller and is not covered by FOSSBilling's rate limiter, which only applies to `/api/*` routes. This allows an attacker to probe the endpoint for valid reset tokens without any per-IP request limiting, attempt counting, or lockout mechanism. The endpoint acts as an oracle, returning a distinguishable response for valid versus invalid tokens (HTTP 200 vs HTTP 302 redirect). An attacker can submit unlimited token guesses to the password reset confirmation endpoint with no throttling applied. However, practical exploitability is significantly mitigated by the current token generation, which uses `hash('sha256', random_bytes(32))`, providing 256 bits of entropy. Tokens also expire after 15 minutes and are deleted after successful use. The same architectural gap applies to other controller-served auth routes, including `/staff/email/:hash` (admin password reset confirmation) and `/client/confirm-email/:hash` (email confirmation). Version 0.8.0 fixes the issue. Some workarounds are available. Configure a reverse proxy (e.g., Nginx, Apache, Cloudflare) to apply per-IP rate limiting to the `/client/reset-password-confirm/*` and `/staff/email/*` paths and/or use a WAF rule to limit request rates to these endpoints.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| FOSSBilling | FOSSBilling |
< 0.8.0 (affected)
|
— |
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
- https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-cqqm-p3x5-9fqg x_refsource_CONFIRM
- https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.0 x_refsource_MISC
Web references (5)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.0 tenable:github.com
- https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-cqqm-p3x5-9fqg tenable:github.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-43926 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-43926 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.0 security-advisories@github.com
- https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-cqqm-p3x5-9fqg security-advisories@github.com
Remediations (16)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blackswan-cybersecurity.com
Cloud Files API activity originating outside legitimate OneDrive/sync processes. Mitigation Steps: Apply all Windows updates immediately (monitor MSRC for an emergency RedSun-specific patch . None released as of April 17, 2026 ). Supplement Defender with a secondary EDR solution (e.g., Huntress) capable of detecting Defender bypasses.
2026-06-08 15:51 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-06-08 15:51 UTC -
web:github.com
CVEfixes: Automated Collection of Vulnerabilities and Their Fixes from Open-Source Software - secureIT-project/CVEfixes
2026-06-08 15:51 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-06-08 15:51 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-06-08 15:51 UTC -
web:support.servicenow.com
Overview The advisories below document publicly disclosed Common Vulnerabilities and Exposures ( CVEs ) in the Now Platform by ServiceNow. Because ServiceNow uses various methods to communicate vulnerability information, patches, and other fixes, customers should review family, security patch , and hotfix release notes, which are available at https://docs.servicenow.com, for a complete list of ...
2026-06-08 15:51 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-06-08 15:51 UTC -
web:www.crowdstrike.com
Microsoft has released security updates for 130 vulnerabilities, including 30 critical, in its May 2026 Patch Tuesday rollout.
2026-06-08 15:51 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-06-08 15:51 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's June 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-06-08 15:51 UTC -
web:cybersecuritynews.com
Microsoft has officially acknowledged a critical zero-day vulnerability in Microsoft Defender, publicly dubbed "RoguePlanet," and confirmed it is actively developing a security patch to address the flaw.
2026-06-19 02:34 UTC -
web:msrc.microsoft.com
Security Update Guide - Microsoft Security Response Center
2026-06-19 02:34 UTC -
web:www.computerworld.com
Microsoft says it is considering a patch for a zero-day vulnerability, dubbed YellowKey, that allows attackers with access to a Windows device to bypass Bitlocker encryption protection and read ...
2026-06-19 02:34 UTC -
web:www.malwarebytes.com
Microsoft says it's working on a fix for an unpatched Defender vulnerability that can give attackers the highest level of access on Windows.
2026-06-19 02:34 UTC -
web:www.oracle.com
This Critical Security Patch Update contains 35 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Security Patch Update and other Oracle Software Security Assurance activities is located at May 2026 Critical Security Patch Update: Executive Summary and Analysis.
2026-06-19 02:34 UTC -
web:www.vulncheck.com
VulnCheck identified 25 CVEs disclosed in 2026 that have been routinely targeted by adversaries and researchers so far this year, drawing from a global body of exploit code and exploitation data.
2026-06-19 02:34 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-43926.json.
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