---
id: "CVE-2026-126305"
page: "https://infrastack.ai/live/CVE-2026-126305"
kind: "vulnerability"
aliases: ["CVE-2026-126305"]
title: "EspoCRM: stored XSS in Knowledge Base lets attacker create admin accounts"
severity: "high"
cvss: 8.5
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["espocrm", "knowledge-base", "package", "self-hosted"]
not_affected_if: ["no-knowledge-base-editors", "patched-version"]
published_at: "2026-11-13T10:17:35+00:00"
first_seen_at: "2026-11-13T10:47:15+00:00"
updated_at: "2026-11-13T10:50:59+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126305", "first_seen_at": "2026-11-13T10:47:15+00:00"}]
exploit_sources: []
---

# EspoCRM: stored XSS in Knowledge Base lets attacker create admin accounts

Link for people: https://infrastack.ai/live/CVE-2026-126305 (this .md is for agents)

EspoCRM before 9.3.11 and 10.x before 10.0.9 let a user with Knowledge Base create or edit access store a JavaScript file and a crafted link in an article. When an administrator clicks that link, the script runs in their session and can create a new administrator account with attacker-chosen credentials.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed EspoCRM version in the application's version or package files; versions below `9.3.11` on the 9.x line, or below `10.0.9` on the 10.x line, are in range.
- Review Knowledge Base users who have create or edit access, since they are the ones who can plant the payload.

## Fix

- EspoCRM 9.x: upgrade to `9.3.11` or later.
- EspoCRM 10.x: upgrade to `10.0.9` or later.

## Timeline

- 2026-11-13T10:47:15+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126305

## Documents

- [advisory] Vendor advisory: github.com https://github.com/espocrm/espocrm/security/advisories/GHSA-j6q5-9jwj-9p8q
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/espocrm-before-10.0.9-stored-xss-via-knowledge-base-article-attachments

## From the sources

EspoCRM before 9.3.11 and 10.x before 10.0.9 contains a stored cross-site scripting vulnerability in Knowledge Base articles that lets users with Knowledge Base create or edit access attach a JavaScript file and add a crafted link to the article body. When an administrator clicks the link, the script runs in their session and can create an administrator account with attacker-chosen credentials.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_