Fireware
CVE-2026-3343
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Output encoding, context-aware escaping
MITRE ATT&CK
2 techniques across 2 tactics: Initial Access, Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS 6.1 (MEDIUM). Attack vector: Network. Complexity: Low. Privileges required: None. User interaction: Required. Exploitation requires authentication. |
| Exploit ScenarioDerived | An attacker (requires authentication) could exploit this vulnerability to compromise the affected system. |
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Alert meAnalysisAIv1 – Mar 12, 2026
Fireware OS Web UI contains a reflected XSS vulnerability that allows attackers to execute arbitrary JavaScript in authenticated administrators' browsers through crafted links, affecting versions 12.7-12.11.7 and 2025.1-2026.1.1. An attacker can leverage this to perform administrative actions or steal session credentials from targeted management users who click malicious links. No patch is currently available.
Earlier versions of this analysis (1)
A reflected cross-site scripting (XSS) vulnerability in the Fireware OS Web UI enabled execution of malicious JavaScript in the context of an authenticated management user's browser when they click on a specially crafted link. [CVSS 6.1 MEDIUM]
RemediationAI
Monitor vendor advisories for a patch. Implement output encoding and Content Security Policy headers. Restrict network access to the affected service where possible.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Classified as CWE-79 (Cross-site Scripting (XSS)). Affects Fireware. A reflected cross-site scripting (XSS) vulnerability in the Fireware OS Web UI enabled execution of malicious JavaScript in the context of an authenticated management user's browser when they click on a specially crafted link.
This vulnerability affects Fireware OS 12.7 up to and including 12.11.7 and 2025.1 up to and including 2026.1.1.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Primary rating from Vendor (5d1c2695-1a31-4499-88ae-e847036fd7e3) · only source for this CVE.
CVSS VectorVendor: 5d1c2695-1a31-4499-88ae-e847036fd7e3
Lifecycle Timeline
2DescriptionCVE.org
A reflected cross-site scripting (XSS) vulnerability in the Fireware OS Web UI enabled execution of malicious JavaScript in the context of an authenticated management user's browser when they click on a specially crafted link.
This vulnerability affects Fireware OS 12.7 up to and including 12.11.7 and 2025.1 up to and including 2026.1.1.
Executive ViewAI
CVE-2026-3343 presents moderate security risk, a cross-site scripting vulnerability rated CVSS 6.1. Attackers could inject scripts to steal sessions or perform actions as authenticated users. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: implement CSP headers, enable HttpOnly cookies, deploy WAF XSS rules.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
Affected Products (CPE)CVE.org
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GitHub PoC
Exploit-DB