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: 0.9%CVSS: 7.5Exploit: None knownExposed services: Not assessed

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
7.5HIGHmedium confidence
EG Risk
34
EG Risk 34/100

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%
EPSS PROB
0.9%
EPSS %ILE
58th
KEV
Not listed

Published

May 4, 2026

Last Modified

August 20, 2026

Advisory Details (8)

Auto-updated Jul 3, 2026
Patch available. Sources: redhat.
redhatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 6",

https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43964.json
redhatMentions a patch (unverified)

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
redhatMentions a patch (unverified)

cve-details

https://access.redhat.com/security/cve/CVE-2026-43964
redhatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:26205
redhatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2026:25932
redhatMentions a patch (unverified)

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 / EcosystemFix (by version range) / 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 rangeFix by version rangeDependents
postfix3.10.1-1 ... 3.9.1-9 (75 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
postfix3.10.1-1 ... 3.9.1-9 (61 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
postfix3.10.3-2 ... 3.10.8-1 (14 versions)
  • every version up to 3.10.10-0+deb13u1: fixed in 3.10.10-0+deb13u1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
postfix3.10.3-2 ... 3.11.0-4 (18 versions)
  • every version up to 3.11.2-1: fixed in 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 / 21× 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 223 total refreshes for this CVE.

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

Related CVEs(same product + same CWE)

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 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 0.9% probability of exploitation in the next 30 days (58th percentile of EPSS-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?
A fix for CVE-2026-43964 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-43964 are linked in the Vendor Advisories panel on this page.

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