SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-101127

Joomla Extension - balbooa.com - Unauthenticated upload filename stored XSS in Balbooa Forms < 2.4.3.4 - The public form upload endpoint validates the uploaded file's extension and detected MIME type, but stores the attacker-supplied original multipart…

HIGH 8.6EPSS 0.33%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.33%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Joomla Extension - balbooa.com - Unauthenticated upload filename stored XSS in Balbooa Forms < 2.4.3.4 - The public form upload endpoint validates the uploaded file's extension and detected MIME type, but stores the attacker-supplied original multipart filename verbatim in `#__baforms_submissions_attachments.name`. A later anonymous form submission associates that temporary attachment with the newly created submission. When an administrator opens the submission, the component's JavaScript retrieves the stored attachment record and concatenates `file.name` directly into an HTML string. The complete string is assigned to `innerHTML`.

CVSS 4.0
8.6 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:L/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/M
EPSS
0.33% probability · 26th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-79
Affected
balbooa/forms
Source
security@joomla.org
EPSS trend
0%3%5%30 September 2026: 0.32%26 October 2026: 0.33%30 September 202626 October 2026

EPSS moved from 0.3% on 30 September 2026 to 0.3% on 26 October 2026.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.