Username enumeration via discrepant REST challenge responses
Published May 15, 2023 · Updated Jun 1, 2026
Information disclosure in SICK AG FTMg sensors with all firmware versions allows remote attackers to enumerate valid usernames via REST. The REST authentication challenge emits observably different responses for valid and invalid usernames, exposing whether an account exists without credentials. Network access to the sensor web server is sufficient; the disclosed information is limited to valid usernames and does not include passwords.
Summary
What happened
Information disclosure in SICK AG FTMg sensors with all firmware versions allows remote attackers to enumerate valid usernames via REST. The REST authentication challenge emits observably different responses for valid and invalid usernames, exposing whether an account exists without credentials. Network access to the sensor web server is sufficient; the disclosed information is limited to valid usernames and does not include passwords.
The record
- CVE
- CVE-2023-23449
- Published
- May 15, 2023
- Updated
- Jun 1, 2026
- Vendor
- SICK AG
- Product
- FTMG-ESD15AXX
- Classifications
- CWE-204, T1087
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 15, 2023CVE publishedPublication date reported by the CVE source.
- Jun 1, 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?
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- Affected versionversion=all firmware versions
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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