Filesystem disclosure via hardcoded UART credentials
Published Dec 9, 2025 · Updated Dec 9, 2025
Hard-coded credentials in Phoenix Contact FL SWITCH 2xxx firmware before 3.50 allow physically proximate attackers to read device files. An undocumented UART port on the PCB accepts the hard-coded user credentials obtained through the related password-generation flaw and exposes parts of the filesystem. Exploitation requires physical access to the appliance and possession of those recovered credentials; no data modification or service interruption is reported.
Summary
What happened
Hard-coded credentials in Phoenix Contact FL SWITCH 2xxx firmware before 3.50 allow physically proximate attackers to read device files. An undocumented UART port on the PCB accepts the hard-coded user credentials obtained through the related password-generation flaw and exposes parts of the filesystem. Exploitation requires physical access to the appliance and possession of those recovered credentials; no data modification or service interruption is reported.
The record
- CVE
- CVE-2025-41696
- Published
- Dec 9, 2025
- Updated
- Dec 9, 2025
- Vendor
- Phoenix Contact
- Product
- FL SWITCH 2204-2TC-2SFX
- Classifications
- CWE-798, T1200, T1005
- Attack vector
- physical
- Privileges
- unauthenticated
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
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
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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