CVE-2026-43964
Analyzed Analyzed - Analysis Complete
Buffer Over-Read in Postfix SMTP Server

Publication date: 2026-05-04

Last updated on: 2026-05-11

Assigner: MITRE

Description
Postfix before 3.8.16, 3.9 before 3.9.10, and 3.10 before 3.10.9 sometimes allows a buffer over-read and process crash via an enhanced status code that lacks text after the third number.
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Meta Information
Published
2026-05-04
Last Modified
2026-05-11
Generated
2026-06-16
AI Q&A
2026-05-05
EPSS Evaluated
2026-06-15
NVD
CVE-2026-43964
Affected Vendors & Products
Showing 3 associated CPEs
Vendor Product Version / Range
postfix postfix to 3.8.16 (exc)
postfix postfix From 3.10.0 (inc) to 3.10.9 (exc)
postfix postfix From 3.9.0 (inc) to 3.9.10 (exc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-193 A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.
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Executive Summary

This vulnerability affects certain versions of Postfix (before 3.8.16, 3.9 before 3.9.10, and 3.10 before 3.10.9). It occurs when an enhanced status code is received that lacks text after the third number, which can cause a buffer over-read and lead to the process crashing.

Impact Analysis

The vulnerability can cause the Postfix process to crash due to a buffer over-read. This results in a denial of service condition, potentially disrupting mail services.

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