CVE-2026-53641

medium

Description

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.0 through 0.7.2 have a stored cross-site scripting (XSS) vulnerability in the client-facing email history views of FOSSBilling. Email HTML content (`content_html`) is rendered into a JavaScript template literal using the `|raw` filter, bypassing all output escaping. An attacker with admin access can inject malicious JavaScript payloads into email content that execute in the browser of any client who views their email history. Version 0.8.0 contains a fix. Some workarounds are available. Restrict admin account access, audit email content in the database for suspicious payloads, and/or monitor client accounts for unusual activity.

References

https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-q6c8-6r72-35f7

Details

Source: Mitre, NVD

Published: 2026-07-06

Updated: 2026-07-06

Risk Information

CVSS v2

Base Score: 3.5

Vector: CVSS2#AV:N/AC:M/Au:S/C:N/I:P/A:N

Severity: Low

CVSS v3

Base Score: 5.4

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Severity: Medium

CVSS v4

Base Score: 4.8

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Severity: Medium

EPSS

EPSS: 0.00043