Authenticated web-server hang via whitespace-only command
Published Dec 9, 2025 · Updated Dec 9, 2025
Resource exhaustion in Phoenix Contact FL SWITCH 2xxx and FL NAT 2xxx firmware before 3.50 allows remote authenticated users to hang the web server. The webshell accepts an empty command made only of whitespace and leaves the server waiting indefinitely for additional request data. Low-privileged webshell access is required, and the reported consequence is loss of web-server availability.
Summary
What happened
Resource exhaustion in Phoenix Contact FL SWITCH 2xxx and FL NAT 2xxx firmware before 3.50 allows remote authenticated users to hang the web server. The webshell accepts an empty command made only of whitespace and leaves the server waiting indefinitely for additional request data. Low-privileged webshell access is required, and the reported consequence is loss of web-server availability.
The record
- CVE
- CVE-2025-41694
- Published
- Dec 9, 2025
- Updated
- Dec 9, 2025
- Vendor
- Phoenix Contact
- Product
- FL SWITCH 2204-2TC-2SFX
- Classifications
- CWE-770, T1499.003
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 9, 2025CVE publishedPublication date reported by the CVE source.
- Dec 9, 2025Record 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=0.0.0 <3.50
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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