Low severity · published Jul 6, 2026
CVE-2026-53640
FOSSBilling missing authorization checks on read-only admin API endpoints expose sensitive staff, client, and redirect data
2.3
CVSS
0.4%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 29% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
FOSSBilling · FOSSBilling
< 0.8.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-53640
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-53640
github.com
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-jqw4-3hj3-8m4f
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