High severity · published Jul 6, 2026
CVE-2026-43918
Suspended or inactive FOSSBilling accounts can retain or regain access through existing sessions, API tokens, and password reset flows
8.7
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, when a client or staff/admin account is suspended or marked inactive, existing authenticated sessions are not invalidated. The session identity loaders in src/di.php (loggedin_client and loggedin_admin) only reject sessions if the backing account record no longer exists in the database. They do not verify that the account's status is still active. This allows a suspended or deactivated user to retain full access until their session naturally expires. This issue has been fixed in version 0.8.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% 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-2026-43918
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-43918
github.com
https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.0
github.com
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-qv6c-v49w-8g2j
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