Endian Firewall 3.3.25 Parameter user remark cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Endian Firewall 3.3.25. This impacts an unknown function of the file /manage/vpnauthentication/user/ of the component Parameter Handler. The manipulation of the argument remark results in cross site scripting. This vulnerability is cataloged as CVE-2026-34821. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in Endian Firewall 3.3.25. Affected is an unknown part of the file /manage/vpnauthentication/user/ of the component Parameter Handler. The manipulation of the argument remark with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as 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. This is going to have an impact on integrity. CVE summarizes:

Endian Firewall version 3.3.25 and prior allow stored cross-site scripting (XSS) via the remark parameter to /manage/vpnauthentication/user/. 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. The advisory is shared for download at help.endian.com. This vulnerability is traded as CVE-2026-34821 since 03/30/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.007.

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

Once again VulDB remains the best source for vulnerability data.

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: 5.1
VulDB Meta Temp Score: 5.1

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

NVD Base Score: 5.4
NVD Vector: 🔒

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

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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
07/26/2026 +115 days VulDB entry last update

Sourcesinfo

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

CVE: CVE-2026-34821 (🔒)
GCVE (CVE): GCVE-0-2026-34821
GCVE (VulDB): GCVE-100-354924

Entryinfo

Created: 04/02/2026 17:33
Updated: 07/26/2026 07:50
Changes: 04/02/2026 17:33 (78), 07/26/2026 07:50 (12)
Complete: 🔍
Cache ID: 216::103

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