Email notification interruption via unchecked SMTP response
Published Nov 14, 2023 · Updated Feb 25, 2026
Unchecked return handling in affected Siemens network-device firmware allows remote attackers to interrupt event email notifications. The event-email SMTP response path fails to check a return value when processing an invalid server reply, leaving later emails unsent. Exploitation requires event email to be configured and network access sufficient to present a malformed SMTP response; the consequence is lost notifications rather than a device-wide outage.
Summary
What happened
Unchecked return handling in affected Siemens network-device firmware allows remote attackers to interrupt event email notifications. The event-email SMTP response path fails to check a return value when processing an invalid server reply, leaving later emails unsent. Exploitation requires event email to be configured and network access sufficient to present a malformed SMTP response; the consequence is lost notifications rather than a device-wide outage.
The record
- CVE
- CVE-2023-44322
- Published
- Nov 14, 2023
- Updated
- Feb 25, 2026
- Vendor
- Siemens
- Product
- SCALANCE WUM763-1 (US)
- Classifications
- CWE-252, T1562.006
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 14, 2023CVE publishedPublication date reported by the CVE source.
- Feb 25, 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=0 <V3.0.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
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Your stack
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