CVE-2026-43964

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.5%, top 58% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.5Exploit: None knownExposed: 0

A fix is available — apply it.

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.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
34(Track)
EG Risk 34/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
43%
KEV
Not listed

Published

May 4, 2026

Last Modified

August 20, 2026

Advisory Details (8)

Auto-updated Jul 3, 2026
Patch available. Sources: redhat.
redhat Patch Available

Affected: Red Hat Enterprise Linux 6",

https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43964.json
redhat Patch Available

2466488 – (CVE-2026-43964) CVE-2026-43964 postfix: buffer over-read via malformed enhanced status code

Affected: Red Hat Enterprise Linux 10

https://bugzilla.redhat.com/show_bug.cgi?id=2466488
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-43964
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:26205
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2026:25932
redhat Patch Available

Affected: Red Hat Enterprise Linux 10.

https://access.redhat.com/errata/RHSA-2026:25930
generic

oss-security - Re: Fwd: [pfx] Postfix stable release 3.11.2 and legacy releases 3.10.9, 3.9.10, 3.8.16

http://www.openwall.com/lists/oss-security/2026/05/04/30
generic

[pfx-ann] Postfix stable release 3.11.2 and legacy releases 3.10.9, 3.9.10, 3.8.16

https://www.mail-archive.com/[email protected]/msg00110.html

Vendor Advisories for CVE-2026-43964(10)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(10)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntupostfix-sqlite (3.10.6-4ubuntu2.1) @ resolute2026-08-23ubuntu
ubuntupostfix-pgsql (3.1.0-3ubuntu0.4+esm4) @ xenial2026-08-23ubuntu
redhatpostfix-2:2.10.1-9.el7_9.12026-08-19redhat
redhatpostfix-2:3.8.5-8.el10_0.12026-08-06redhat
redhatpostfix-2:3.5.8-1.el8_4.12026-08-06redhat
redhatpostfix-2:3.5.8-4.el8_8.12026-08-06redhat
redhatpostfix-2:3.5.8-4.el8_6.12026-08-06redhat
redhatpostfix-2:3.5.25-3.el9_82026-06-16redhat
redhatpostfix-2:3.5.8-8.el8_102026-06-15redhat
redhatpostfix-2:3.8.5-10.el10_22026-06-15redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
postfix3.10.1-1 ... 3.9.1-9 (75 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
postfix3.10.1-1 ... 3.9.1-9 (60 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
postfix3.10.3-2 ... 3.10.8-1 (14 versions)3.10.10-0+deb13u1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
postfix3.10.3-2 ... 3.11.0-4 (18 versions)3.11.2-1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(2)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 6× in last 7d / 27× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 211 total refreshes for this CVE.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-17 19:31 UTCEPSS rescore
  3. 2026-09-16 14:08 UTCEPSS rescore
  4. 2026-09-16 05:15 UTCEPSS rescore
  5. 2026-09-13 16:47 UTCEPSS rescore
  6. 2026-09-12 15:01 UTCEPSS rescore
  7. 2026-09-11 14:53 UTCEPSS rescore
  8. 2026-09-11 09:37 UTCEPSS rescore
  9. 2026-09-10 09:34 UTCEPSS rescore
  10. 2026-09-08 22:00 UTCEPSS rescore
  11. 2026-09-07 16:01 UTCEPSS rescore
  12. 2026-09-06 13:47 UTCEPSS rescore
  13. 2026-09-04 05:06 UTCEPSS rescore
  14. 2026-09-02 14:12 UTCEPSS rescore
  15. 2026-09-01 13:54 UTCEPSS rescore
  16. 2026-08-30 19:17 UTCEPSS rescore
  17. 2026-08-30 01:22 UTCEPSS rescore
  18. 2026-08-28 21:41 UTCEPSS rescore
  19. 2026-08-27 14:25 UTCEPSS rescore
  20. 2026-08-26 14:46 UTCEPSS rescore
  21. 2026-08-25 13:49 UTCEPSS rescore
  22. 2026-08-23 21:16 UTCEG score recompute
  23. 2026-08-23 21:16 UTCVendor advisory
  24. 2026-08-23 21:16 UTCGHSA enrichment
  25. 2026-08-23 00:19 UTCEPSS rescore
Show 75 more
  1. 2026-08-21 23:49 UTCEPSS rescore
  2. 2026-08-20 22:55 UTCEPSS rescore
  3. 2026-08-20 13:58 UTCVendor advisory
  4. 2026-08-20 13:58 UTCGHSA enrichment
  5. 2026-08-20 12:43 UTCEG score recompute
  6. 2026-08-20 12:43 UTCVendor advisory
  7. 2026-08-20 12:43 UTCGHSA enrichment
  8. 2026-08-19 17:04 UTCEPSS rescore
  9. 2026-08-18 13:48 UTCEPSS rescore
  10. 2026-08-17 13:47 UTCEPSS rescore
  11. 2026-08-17 13:06 UTCEG score recompute
  12. 2026-08-17 13:06 UTCVendor advisory
  13. 2026-08-17 13:06 UTCGHSA enrichment
  14. 2026-08-16 14:56 UTCEPSS rescore
  15. 2026-08-16 05:02 UTCEG score recompute
  16. 2026-08-16 05:02 UTCVendor advisory
  17. 2026-08-16 05:02 UTCGHSA enrichment
  18. 2026-08-16 02:14 UTCEPSS rescore
  19. 2026-08-15 01:30 UTCEPSS rescore
  20. 2026-08-14 16:43 UTCVendor advisory
  21. 2026-08-14 16:43 UTCGHSA enrichment
  22. 2026-08-14 03:37 UTCEG score recompute
  23. 2026-08-14 03:37 UTCVendor advisory
  24. 2026-08-14 03:37 UTCGHSA enrichment
  25. 2026-08-13 22:00 UTCEPSS rescore
  26. 2026-08-13 06:35 UTCVendor advisory
  27. 2026-08-13 06:35 UTCGHSA enrichment
  28. 2026-08-12 17:14 UTCEG score recompute
  29. 2026-08-12 17:14 UTCVendor advisory
  30. 2026-08-12 17:14 UTCGHSA enrichment
  31. 2026-08-12 13:51 UTCEPSS rescore
  32. 2026-08-11 16:08 UTCEG score recompute
  33. 2026-08-11 16:08 UTCVendor advisory
  34. 2026-08-11 16:08 UTCGHSA enrichment
  35. 2026-08-11 13:43 UTCEPSS rescore
  36. 2026-08-11 01:39 UTCEG score recompute
  37. 2026-08-11 01:39 UTCVendor advisory
  38. 2026-08-11 01:39 UTCGHSA enrichment
  39. 2026-08-11 00:00 UTCEPSS rescore
  40. 2026-08-10 04:34 UTCVendor advisory
  41. 2026-08-10 04:34 UTCGHSA enrichment
  42. 2026-08-09 15:38 UTCEG score recompute
  43. 2026-08-09 15:38 UTCVendor advisory
  44. 2026-08-09 15:38 UTCGHSA enrichment
  45. 2026-08-09 13:46 UTCEPSS rescore
  46. 2026-08-09 02:43 UTCEG score recompute
  47. 2026-08-09 02:43 UTCVendor advisory
  48. 2026-08-09 02:43 UTCGHSA enrichment
  49. 2026-08-08 16:37 UTCEPSS rescore
  50. 2026-08-08 01:21 UTCEG score recompute
  51. 2026-08-08 01:21 UTCVendor advisory
  52. 2026-08-08 01:21 UTCGHSA enrichment
  53. 2026-08-07 12:25 UTCVendor advisory
  54. 2026-08-07 12:25 UTCGHSA enrichment
  55. 2026-08-07 12:09 UTCVendor advisory
  56. 2026-08-07 12:09 UTCGHSA enrichment
  57. 2026-08-07 02:34 UTCEG score recompute
  58. 2026-08-07 02:34 UTCVendor advisory
  59. 2026-08-07 02:34 UTCGHSA enrichment
  60. 2026-08-06 13:46 UTCEPSS rescore
  61. 2026-08-06 13:39 UTCVendor advisory
  62. 2026-08-06 13:39 UTCGHSA enrichment
  63. 2026-08-06 12:34 UTCVendor advisory
  64. 2026-08-06 12:34 UTCGHSA enrichment
  65. 2026-08-06 11:25 UTCVendor advisory
  66. 2026-08-06 11:25 UTCGHSA enrichment
  67. 2026-08-05 22:28 UTCEG score recompute
  68. 2026-08-05 22:28 UTCVendor advisory
  69. 2026-08-05 22:28 UTCGHSA enrichment
  70. 2026-08-05 19:17 UTCEPSS rescore
  71. 2026-08-04 15:10 UTCEPSS rescore
  72. 2026-08-04 10:38 UTCEPSS rescore
  73. 2026-08-03 20:01 UTCEG score recompute
  74. 2026-08-03 20:01 UTCVendor advisory
  75. 2026-08-03 20:01 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-43964?
CVE-2026-43964 is a high vulnerability published on May 4, 2026. 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.
When was CVE-2026-43964 disclosed?
CVE-2026-43964 was first published in the National Vulnerability Database on May 4, 2026, with the most recent update on August 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43964 actively exploited?
CVE-2026-43964 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 57.5% of all scored CVEs.
What is the CVSS score of CVE-2026-43964?
CVE-2026-43964 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-43964?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43964, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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