CVE-2026-43964
📛 CVE Title
CVE-2026-43964
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- mitre
- CVSS severity
- LOW
- CVSS score
- 3.7 / 10
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L- Effective score
- 3.7 / 10 LOW source: CNA overview
- MSRC score
- 3.7 / 10 LOW MS rating: Low
- CWE(s)
-
CWE-193 - Reserved
- 2026-05-04
- Published
- 2026-05-04 20:10 UTC
- Last updated
- 2026-05-05 00:21 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/43xxx/CVE-2026-43964.json
- Linked Threat
- CVE-2026-43964 — CVE-2026-43964
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-04 19:16:07 UTC
- NVD last modified
- 2026-05-11 21:17:31 UTC
- NVD CVSS v3.1
- 3.7 / 10 LOW source: cve@mitre.org
- NVD CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L- Exploitability subscore
- 2.2 / 10
- Impact subscore
- 1.4 / 10
- EPSS score
- 0.0005 (probability of exploitation in next 30 days)
- EPSS percentile
- 16.46% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 08:46 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-27115 - Assigner
- mitre
- Published
- May 4, 2026, 6:10:10 PM
- Updated
- May 4, 2026, 10:21:13 PM
- EUVD base score (CVSS 3.1)
-
3.7 / 10
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - EUVD-reported EPSS
- 0.0500
- Vendors
- Postfix
- Products
-
Postfix (3.9 <3.9.10)Postfix (3.10 <3.10.9)Postfix (2.3 <3.8.16)
ENISA 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.
EUVD references (1)
Microsoft Security Response Center MSRC
Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-08-15 03:01 UTC (source: CVRF).
- MS severity
- Low
- MS CVSS base score
- 3.7 / 10 (temporal 3.7)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - Release
- 2026-May
Microsoft remediations / KB articles (2)
- CBL-Mariner Releases — Vendor Fix / Security Update (fixed build 3.9.11-1)
- https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / CBL-Mariner Releases
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Postfix | Postfix |
2.3 (affected),
3.9 (affected),
3.10 (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:*
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
MITRE references (1) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
Web references (11)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- MSRC update guide: CVE-2026-43964 msrc
- None Available msrc
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-27115 rapid7:euvd.enisa.europa.eu
- http://cwe.mitre.org/data/definitions/193.html rapid7:cwe.mitre.org
- https://attackerkb.com/topics/CVE-2026-43964 rapid7:attackerkb.com
- https://ubuntu.com/security/notices/USN-8253-1 rapid7:ubuntu.com
- https://www.openwall.com/lists/oss-security/2026/05/04/25 rapid7:www.openwall.com
- https://www.cve.org/CVERecord?id=CVE-2026-43964 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
- http://www.openwall.com/lists/oss-security/2026/05/04/30 tenable:www.openwall.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-43964 tenable:nvd.nist.gov
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- http://www.openwall.com/lists/oss-security/2026/05/04/30 af854a3a-2127-422b-91ae-364da2661108 Mailing ListThird Party Advisory
- https://www.mail-archive.com/postfix-announce@postfix.org/msg00110.html cve@mitre.org Mailing ListThird Party Advisory
Remediations (17)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cisa.gov
Update (08/12/2025): CISA has updated this alert to provide clarification on identifying Exchange Servers on an organization's networks and provided further guidance on running the Microsoft Exchange Health Checker. Update (08/07/2025): CISA issued Emergency Directive (ED) 25-02: Mitigate Microsoft Exchange Vulnerability in response to CVE -2025-53786
2026-05-23 21:15 UTC -
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-23 21:15 UTC -
web:krebsonsecurity.com
Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.
2026-05-23 21:15 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-05-23 21:15 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-23 21:15 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-23 21:15 UTC -
web:www.msn.com
Original story: Microsoft has released an emergency patch for a vulnerability in the company's Office programs that's already being exploited by hackers.
2026-05-23 21:15 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-23 21:15 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-23 21:15 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 21:15 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-06-03 07:49 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-06-03 07:49 UTC -
web:nvd.nist.gov
The NVD is the U.S. government repository of standards based vulnerability management data represented using the Security Content Automation Protocol (SCAP). This data enables automation of vulnerability management, security measurement, and compliance. The NVD includes databases of security checklist references, security-related software flaws, product names, and impact metrics. For ...
2026-06-03 07:49 UTC -
web:support.servicenow.com
Overview The advisories below document publicly disclosed Common Vulnerabilities and Exposures ( CVEs ) in the Now Platform by ServiceNow. Because ServiceNow uses various methods to communicate vulnerability information, patches, and other fixes, customers should review family, security patch , and hotfix release notes, which are available at https://docs.servicenow.com, for a complete list of ...
2026-06-03 07:49 UTC -
web:www.crowdstrike.com
Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.
2026-06-03 07:49 UTC -
web:www.virustotal.com
VirusTotal is a platform for scanning files and URLs for viruses, malware, and other threats using multiple antivirus engines.
2026-06-03 07:49 UTC -
web:www.vulncheck.com
VulnCheck identified 25 CVEs disclosed in 2026 that have been routinely targeted by adversaries and researchers so far this year, drawing from a global body of exploit code and exploitation data.
2026-06-03 07:49 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-43964.json.
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