Unauthenticated service interruption and disclosure via SMTP overflow
Published Aug 13, 2026 · Updated Aug 13, 2026
Stack-based buffer overflow in IBM Power operating system 7.3 through 7.6 allows remote attackers to disrupt SMTP and expose sensitive data. IBM identifies SMTP as the affected component but has not disclosed the parser or operation that writes beyond the stack buffer. No authentication or user interaction is required; the documented consequences are service interruption and limited disclosure.
Summary
What happened
Stack-based buffer overflow in IBM Power operating system 7.3 through 7.6 allows remote attackers to disrupt SMTP and expose sensitive data. IBM identifies SMTP as the affected component but has not disclosed the parser or operation that writes beyond the stack buffer. No authentication or user interaction is required; the documented consequences are service interruption and limited disclosure.
The record
- CVE
- CVE-2026-16815
- Published
- Aug 13, 2026
- Updated
- Aug 13, 2026
- Vendor
- IBM
- Product
- IBM i
- Classifications
- CWE-787, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 13, 2026CVE publishedPublication date reported by the CVE source.
- Aug 13, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=7.3
- Affected versionversion=7.4
- Affected versionversion=7.5
- Affected versionversion=7.6
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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