CVE-2026-42840 ERPNext 16.16.0 - Stored XSS in POS customer section via unescaped template literals
Authenticated users can inject malicious scripts into customer fields, leading to stored XSS execution in the POS interface for other operators.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-42840?
CVE-2026-42840 is a medium-severity cross-site scripting vulnerability in Frappe ERPNext, published on 3 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
An authenticated user can persist arbitrary HTML/JavaScript in the email_id or mobile_no fields of a Customer record and trigger unescaped rendering in the Point of Sale (POS) interface for every operator who selects that customer. This issue affects ERPNext: 16.16.0.
Weakness: CWE-79
Which versions are affected by CVE-2026-42840?
How do I fix CVE-2026-42840?
No fix has been published for CVE-2026-42840 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-42840 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42840 exists.
Sources
Also known as GHSA-w2pq-xvqr-7fqw.