CVE-2026-111048

HIGH
MEDIUM Priority: 0.02 BB Relevance: 57/100
Published: 2026-11-02 Modified: 2026-11-03 First seen: 2026-11-02 Status: active

Attack Surface

Network Low Complexity Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: Active
S: X
AT: None
VC: High
VI: High
VA: None

Description

FOSSBilling is an open source billing and client-management platform. From 0.1.0 until 0.8.9, the admin/support/note_create endpoint stores the note parameter without sanitization in the support_ticket_note table, and src/modules/Support/templates/admin/mod_support_tickets.html.twig renders each stored support ticket note through innerHTML in the admin ticket list. A staff user with only the support.manage_tickets permission can store HTML or JavaScript that executes when another staff member opens the ticket notes. The script runs with the viewing staff member's session and privileges, can read a CSRF token and accessible client or invoice data, and can perform administrative actions available to the viewer, including a Super Administrator. The ticket detail page is not affected because its Twig rendering uses autoescaping. This issue is fixed in version 0.8.9.

Affected Software (2)

VendorProductVersion
FOSSBilling FOSSBilling >= 0.1.0, < 0.8.9
FOSSBilling FOSSBilling >= 0.1.0, < 0.8.9

Bug Bounty Relevance

57 / 100
✓ Network accessible
✓ Low complexity

CVSS Score

8.4 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.28%
Raw Score 0.002780
Percentile 20.5%
Date 2026-11-13

EPSS Trend

2026-11-13
0.00278
2026-11-12
0.00278
2026-11-10
0.00278
2026-11-09
0.00278
2026-11-08
0.00278
2026-11-07
0.00278
2026-11-06
0.00278
2026-11-05
0.00278
2026-11-04
0.00278
2026-11-03
0.00278

Intelligence Sources

mitre ref →
nvd ref →