CVE-2026-40495 (GCVE-0-2026-40495)
Vulnerability from cvelistv5 – Published: 2026-06-03 19:38 – Updated: 2026-06-04 13:50
VLAI
EPSS
VEX
Title
FOSSBilling version exposed via asset cache buster
Summary
FOSSBilling is a free, open-source billing and client management system. Versions prior to 0.8.0 leak the exact system version through asset cache buster parameters in HTML output, bypassing the `hide_version_public` security setting. The FOSSBilling version is embedded in the query string of every `<script>` and `<link>` tag generated by the `script_tag` and `stylesheet_tag` Twig filters. This information is visible to all visitors — including unauthenticated guests — on every page, regardless of whether the `hide_version_public` setting is enabled. The `X-FOSSBilling-Version` HTTP header and the `guest.system.version` API endpoint correctly honour the `hide_version_public` setting, but the asset cache buster parameters were overlooked. Knowledge of the exact FOSSBilling version makes it significantly easier for malicious actors to identify known vulnerabilities applicable to a given installation and craft targeted exploits. While not a direct vulnerability on its own, it undermines the intended protection offered by the `hide_version_public` setting and facilitates reconnaissance. Version 0.8.0 contains a patch. There is no practical workaround that removes the version from asset URLs without modifying source code.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-04 13:49 UTC
CWE
- CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/FOSSBilling/FOSSBilling/securi… | x_refsource_CONFIRM |
| https://github.com/FOSSBilling/FOSSBilling/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| FOSSBilling | FOSSBilling |
Affected:
< 0.8.0
|
guessed |
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