CVE-2026-42840Public exploitNetwork attack vector

Stored XSS via unescaped customer details

Published Jun 3, 2026 · Updated Jun 3, 2026

Stored XSS in Frappe ERPNext 16.16.0 allows remote authenticated users to execute JavaScript when POS operators select a crafted customer. set_customer_info stores untrusted email_id or mobile_no values, and update_customer_section embeds them in a template passed to jQuery .html() without HTML escaping. Any authenticated account can reach the whitelisted setter, but execution requires a POS operator to select the poisoned Customer record; the script runs in that operator's browser.

CVSS severity5.1
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Frappe ERPNext 16.16.0 allows remote authenticated users to execute JavaScript when POS operators select a crafted customer. set_customer_info stores untrusted email_id or mobile_no values, and update_customer_section embeds them in a template passed to jQuery .html() without HTML escaping. Any authenticated account can reach the whitelisted setter, but execution requires a POS operator to select the poisoned Customer record; the script runs in that operator's browser.

The record

CVE
CVE-2026-42840
Published
Jun 3, 2026
Updated
Jun 3, 2026
Vendor
Frappe Technologies Pvt. Ltd.
Product
ERPNext
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=16.16.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Frappe Technologies Pvt. Ltd. · ERPNextversion=16.16.0

Published CVSS scores

5.1Fluid AttacksCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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