What is CVE-2026-53640?
FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, low-privileged staff accounts may read sensitive data via admin API endpoints that lack permission checks. While sibling write endpoints correctly enforce fine-grained permissions, the corresponding read endpoints have no authorization guards. Version 0.8.0 contains a fix. Some workarounds are available. Restrict staff accounts to only those who need access to sensitive data and/or use a reverse proxy or WAF to restrict access to the affected endpoints.
The record classifies CVE-2026-53640 under weakness classes CWE-200, CWE-862. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 91 days ago.
Severity and exploitation probability
- CVSS v4.0 base score
- 2.3 — Low (derived from score)
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - EPSS (FIRST)
- 0.2% probability of exploitation in the next 30 days, higher than 13.2% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 1.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-07-06, last modified 2026-07-07
Is CVE-2026-53640 being exploited?
It currently carries a trending score of 33 in the Threadlinqs vulnerability feed.
Affected products and versions
- FOSSBilling: FOSSBilling
How to fix CVE-2026-53640
No vendor patch reference has been recorded for CVE-2026-53640 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-53640
No threat campaign in the Threadlinqs corpus currently references CVE-2026-53640, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.
Sources
Enriched from CVE.org, NVD, FIRST EPSS. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.