FOSSBilling: Unauthenticated attacker can probe existence of arbitrary files via guest/system/template_exists
FOSSBilling is an open source billing and client-management platform. From 0.1.0 until 0.8.7, the unauthenticated api/guest/system/template_exists endpoint permits path traversal because templateExists uses Path::join on the attacker-controlled file parameter without rejecting .. sequences or verifying that the resolved path remains inside the active theme directory. The trigger is an unauthenticated request to guest/system/template_exists containing traversal sequences in the file parameter. An attacker can submit traversal sequences in the file parameter and observe the returned boolean to determine whether arbitrary files or directories exist on the server. The oracle does not disclose file contents. This issue is fixed in version 0.8.7.
CVE-2026-111053
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-111053
FOSSBilling
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "FOSSBilling",
"product": "FOSSBilling",
"versions": [
{
"status": "affected",
"version": ">= 0.1.0, < 0.8.7"
}
]
}
]- Related CVEs
- CVE-2026-111053
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #38961 · Revision 1
- Added to Heist Feed
- Publisher date