HOMEVULNERABILITIESCVE-2026-3343
MEDIUM

CVE-2026-3343

CWE-79Published: March 3, 2026· Updated: Mar 4, 2026

6.1
CVSS v3.1
EPSS:0.08%probability of exploitation in 30 daysPercentile:23.0th

Official Description

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.

NVD Source

Technical Analysis

CVE-2026-3343 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeChanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected Vendors & Products

watchguard37 products
firewarefirebox m270firebox m290firebox m370firebox m390firebox m440firebox m4600firebox m470firebox m4800firebox m5600firebox m570firebox m5800+25 more
Source: NVD CPE · 37 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (1)

Quick Facts

CVE IDCVE-2026-3343
CVSS Score6.1 / 10
SeverityMEDIUM
WeaknessCWE-79
CISA KEVNo
EPSS (30d)0.08%
Affected1 vendor
PublishedMar 3, 2026

Related CVEs (CWE-79)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-3343 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.