Admin-enabled Telnet access via hardcoded credentials
Published Jul 9, 2024 · Updated Aug 22, 2025
Hardcoded credentials in ifm SmartPLC AC14xx and AC4xxS firmware 4.3.17 and earlier allow remote authenticated users to access Telnet. A high-privilege management function enables a Telnet service whose authentication logic accepts credentials embedded in the firmware. Exploitation requires high-privilege remote access to enable Telnet; the accepted credentials then expose the device command interface.
Summary
What happened
Hardcoded credentials in ifm SmartPLC AC14xx and AC4xxS firmware 4.3.17 and earlier allow remote authenticated users to access Telnet. A high-privilege management function enables a Telnet service whose authentication logic accepts credentials embedded in the firmware. Exploitation requires high-privilege remote access to enable Telnet; the accepted credentials then expose the device command interface.
The record
- CVE
- CVE-2024-28751
- Published
- Jul 9, 2024
- Updated
- Aug 22, 2025
- Vendor
- ifm electronic GmbH
- Product
- SmartPLC AC14xx Firmware
- Classifications
- CWE-798, T1078
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- Jul 9, 2024CVE publishedPublication date reported by the CVE source.
- Aug 22, 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 <=4.3.17
- Affected versionversion=0 <=V4.3.17
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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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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