CVE-2026-43964 (GCVE-0-2026-43964)

Vulnerability from cvelistv5 – Published: 2026-05-04 18:10 – Updated: 2026-06-30 12:08
VLAI
Summary
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.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
Postfix Postfix Affected: 2.3 , < 3.8.16 (custom)
Affected: 3.9 , < 3.9.10 (custom)
Affected: 3.10 , < 3.10.9 (custom)
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Red Hat Red Hat Enterprise Linux AppStream (v. 10)     cpe:/o:redhat:enterprise_linux:10.2
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Red Hat Red Hat Enterprise Linux AppStream (v. 8)     cpe:/a:redhat:enterprise_linux:8::appstream
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Red Hat Red Hat Enterprise Linux AppStream (v. 9)     cpe:/a:redhat:enterprise_linux:9::appstream
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Red Hat Red Hat Enterprise Linux BaseOS (v. 8)     cpe:/o:redhat:enterprise_linux:8::baseos
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Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.