CVE-2026-53575: EspoCRM: Persistent XSS via CSP nonce injection in applicationName setting by admin user
EspoCRM is an open source customer relationship management application. Prior to 9.3.9, an authenticated administrator can place crafted content in the applicationName setting through CSP nonce injection. The persistent injection is inserted into the main application page without escaping, allowing attacker-controlled JavaScript to run in users' sessions and leak page data, including unsaved user input. This issue is fixed in version 9.3.9.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
EspoCRMto a version that resolves this vulnerability.Fixed in 9.3.9
Event History
Frequently Asked Questions
Who can exploit this issue?
An authenticated EspoCRM administrator is required to set a crafted applicationName value. Exploitation does not require user interaction from the attacker after the malicious value has been stored.
Which users are at risk from a successful exploit?
Users who load the main application page can have attacker-controlled JavaScript execute in their sessions. The script can leak page data, including unsaved user input.
What versions should be remediated?
EspoCRM versions prior to 9.3.9 are affected. Upgrade to version 9.3.9, which fixes the issue.
How can I determine whether an instance may already be affected?
Review the applicationName setting for crafted or unexpected content, since the vulnerable setting is stored persistently and inserted into the main application page without escaping.