---
id: CVE-2026-105987
title: Stored XSS in KGS Software tia Viewer
summary: "KGS Software tia Viewer is vulnerable to Stored XSS via the annotation API.\_Due to the lack of input validation, an authenticated attacker can inject arbitrary JavaScript payload into a stickynote annotation. When any user opens the docu…"
severity: medium
cvss: 5.1
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N'
cvssSource: cna
cwe:
  - CWE-79
vendor: KGS Software
product: tia Viewer
affected:
  - tia_viewer < 1.2.8
published: '2026-10-27'
updated: '2026-10-27'
sourceUpdated: '2026-10-27T14:19:02.333Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-105987'
references:
  - url: 'https://cert.pl/en/posts/2026/10/CVE-2026-105987'
  - url: 'https://www.kgs-software.com/en/products/tia-viewer'
tags:
  - cve.org
ingestedAt: '2026-10-27T16:11:59.463Z'
---

## Overview

KGS Software tia Viewer is vulnerable to Stored XSS via the annotation API. Due to the lack of input validation, an authenticated attacker can inject arbitrary JavaScript payload into a stickynote annotation. When any user opens the document, the viewer renders the annotation and the browser executes the payload. This may lead to compromising the user's session.
This issue has been fixed in version 1.2.8.

## Affected

- `tia_viewer < 1.2.8`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.