CVE-2026-86136Network attack vector

File disclosure and crash via unchecked session authorization

Published Sep 29, 2026 · Updated Sep 29, 2026

Missing authorization in WatchGuard Fireware OS wgagent allows remote authenticated users to read daemon-accessible files and crash the process. The session initialization function accepts a crafted management API request without enforcing the privileges required for that operation. Read-only or guest administrator access is sufficient; disclosure is limited to files readable by wgagent, while the crash interrupts that daemon.

CVSS severityUnavailable
Unscored
EPSS probability0.30%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in WatchGuard Fireware OS wgagent allows remote authenticated users to read daemon-accessible files and crash the process. The session initialization function accepts a crafted management API request without enforcing the privileges required for that operation. Read-only or guest administrator access is sufficient; disclosure is limited to files readable by wgagent, while the crash interrupts that daemon.

The record

CVE
CVE-2026-86136
Published
Sep 29, 2026
Updated
Sep 29, 2026
Vendor
WatchGuard Technologies, Inc.
Product
Fireware OS
Classifications
T1499.004, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 29, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 29, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=12.0 <12.12.3
  2. Affected versionversion=12.0 <12.5.21
  3. Affected versionversion=2025.0 <2026.2.3
  4. Affected versionversion=2026.0 <2026.3.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

WatchGuard Technologies, Inc. · Fireware OSversion=12.0 <12.12.3; version=12.0 <12.5.21; version=2025.0 <2026.2.3; version=2026.0 <2026.3.2

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application or System Exploitation
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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