Endian Firewall 3.3.25 Parameter /cgi-bin/proxyuser.cgi User cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability was found in Endian Firewall 3.3.25. It has been classified as problematic. This issue affects some unknown processing of the file /cgi-bin/proxyuser.cgi of the component Parameter Handler. This manipulation of the argument User causes cross site scripting. The identification of this vulnerability is CVE-2026-34813. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability has been found in Endian Firewall 3.3.25 and classified as problematic. Affected by this vulnerability is an unknown code block of the file /cgi-bin/proxyuser.cgi of the component Parameter Handler. The manipulation of the argument user with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

Endian Firewall version 3.3.25 and prior allow stored cross-site scripting (XSS) via the user parameter to /cgi-bin/proxyuser.cgi. An authenticated attacker can inject arbitrary JavaScript that is stored and executed when other users view the affected page.

The weakness was shared by Alex Williams. It is possible to read the advisory at help.endian.com. This vulnerability is known as CVE-2026-34813 since 03/30/2026. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.9

VulDB Base Score: 3.5
VulDB Temp Score: 3.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.4
CNA Vector (VulnCheck): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/30/2026 CVE reserved
04/02/2026 +3 days Advisory disclosed
04/02/2026 +0 days VulDB entry created
04/02/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: help.endian.com
Researcher: Alex Williams
Status: Confirmed

CVE: CVE-2026-34813 (🔒)
GCVE (CVE): GCVE-0-2026-34813
GCVE (VulDB): GCVE-100-354919

Entryinfo

Created: 04/02/2026 17:32
Changes: 04/02/2026 17:32 (78)
Complete: 🔍
Cache ID: 216::103

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