# CVE-2026-34819: Endian Firewall stored XSS in openvpnclient.cgi

Source: https://junglewise.ai/threats/cve-2026-34819-endian-firewall-stored-xss-in-openvpnclient-cgi  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-02. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2026-34819 · Severity: medium · CVSS 6.4 · Published 2026-04-02

Endian Firewall, a security appliance used to protect networks, contains a vulnerability that allows an authorized user to inject malicious scripts into the management interface. When other administrators view the affected configuration page, these scripts can execute automatically in their browser. This could lead to unauthorized actions being performed on behalf of other administrators or the theft of sensitive session information.

Technologies: [Endian Firewall Community](https://junglewise.ai/threats/technologies/firewall-community). Vendors: [Endian](https://junglewise.ai/threats/vendors/endian).

## Quick answers

**Is CVE-2026-34819 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-34819 being exploited in the wild.

**How severe is CVE-2026-34819?** Medium severity, with a CVSS score of 6.4, published 2 April 2026.

**Which products and versions are affected?** Endian Firewall Community <= 3.3.25.

**Is there a fix for CVE-2026-34819?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-34819 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-34819?** Check whether you run Endian Firewall Community at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stored cross-site scripting (XSS) vulnerability exists in Endian Firewall version 3.3.25 and earlier. The flaw is located in the '/cgi-bin/openvpnclient.cgi' component, which fails to properly neutralize user-supplied input in the 'REMARK' parameter. An authenticated attacker with network access to the management interface can submit a crafted request containing malicious JavaScript. This script is then stored on the server and executed in the context of any user (typically an administrator) who subsequently visits the OpenVPN client configuration page. This can result in session hijacking or unauthorized configuration changes.

## Affected products

- Endian Firewall Community <= 3.3.25

## Timeline

- 2026-04-02: advisory: Initial advisory published by VulnCheck
- 2026-04-02: disclosed: CVE-2026-34819 published

## References

- [https://help.endian.com/hc/en-us/sections/360004371358-Community](https://help.endian.com/hc/en-us/sections/360004371358-Community)
- [https://www.vulncheck.com/advisories/endian-firewall-cgi-bin-openvpnclient-cgi-remark-stored-cross-site-scripting](https://www.vulncheck.com/advisories/endian-firewall-cgi-bin-openvpnclient-cgi-remark-stored-cross-site-scripting)

## Related threats

- [Endian Firewall stored XSS in remark parameter](https://junglewise.ai/threats/cve-2026-34823-endian-firewall-stored-xss-in-remark-parameter)
- [Endian Firewall stored XSS in certificate management interface](https://junglewise.ai/threats/cve-2026-34822-endian-firewall-stored-xss-in-certificate-management-interface)
- [Endian Firewall stored XSS in VPN user remark parameter](https://junglewise.ai/threats/cve-2026-34821-endian-firewall-stored-xss-in-vpn-user-remark-parameter)
- [Endian Firewall stored XSS in IPsec remark parameter](https://junglewise.ai/threats/cve-2026-34820-endian-firewall-stored-xss-in-ipsec-remark-parameter)
- [Endian Firewall stored XSS in dnsmasq local domains remark parameter](https://junglewise.ai/threats/cve-2026-34818-endian-firewall-stored-xss-in-dnsmasq-local-domains-remark)