Internal resource access via unvalidated MQTT URI
Published Jul 30, 2026 · Updated Jul 30, 2026
Server-side request forgery in Phoenix Contact CHARX SEC-3xxx firmware before 1.9.1 allows remote attackers to access internal resources via MQTT. The MQTT service dereferences an attacker-controlled URI without validation, while the resulting response creates a new system-configuration entry. No authentication is required; direct impact is limited to integrity and availability loss, while code execution as user-app requires another vulnerability.
Summary
What happened
Server-side request forgery in Phoenix Contact CHARX SEC-3xxx firmware before 1.9.1 allows remote attackers to access internal resources via MQTT. The MQTT service dereferences an attacker-controlled URI without validation, while the resulting response creates a new system-configuration entry. No authentication is required; direct impact is limited to integrity and availability loss, while code execution as user-app requires another vulnerability.
The record
- CVE
- CVE-2026-44091
- Published
- Jul 30, 2026
- Updated
- Jul 30, 2026
- Vendor
- Phoenix Contact
- Product
- CHARX SEC-3100
- Classifications
- CWE-501, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 30, 2026CVE publishedPublication date reported by the CVE source.
- Jul 30, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1.0.0 <1.9.1
What conditions does exploitation require?
What is affected?
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.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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