CVE-2026-28364

HIGHNVD 7.87.9▲
EchelonGraph scoreMEDIUM confidence

Score 7.9 from GitHub Security Advisory (severity: HIGH) published 2026-02-27. NVD baseline CVSS 7.8; sources differ by 0.1.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
7.9EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In OCaml before 4.14.3 and 5.x before 5.4.1, a buffer over-read in Marshal deserialization (runtime/intern.c) enables remote code execution through a multi-phase attack chain. The vulnerability stems from missing bounds validation in the readblock() function, which performs unbounded memcpy() operations using attacker-controlled lengths from crafted Marshal data.

CVSS v3
7.8
EG Score
7.9(medium)
EG Risk
36(Track)
EG Risk 36/100SSVC: 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
Severity79% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
11%
KEV
Not listed

Published

February 27, 2026

Last Modified

July 15, 2026

Advisory Details (5)

Auto-updated Jul 1, 2026
Patch available. Sources: redhat.
redhat

Affected: Red Hat Enterprise Linux 10",

https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-28364.json
redhat

2443348 – (CVE-2026-28364) CVE-2026-28364 ocaml: OCaml: Remote code execution via buffer over-read in Marshal deserialization

https://bugzilla.redhat.com/show_bug.cgi?id=2443348
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-28364
generic

OSV - Open Source Vulnerabilities

https://osv.dev/vulnerability/OSEC-2026-01
generic

security-advisories/2026/OSEC-2026-01.json at generated-osv · ocaml/security-advisories · GitHub

https://github.com/ocaml/security-advisories/blob/generated-osv/2026/OSEC-2026-01.json

Vendor Advisories for CVE-2026-28364(1)

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

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
ocaml4.11.1-4 ... 5.5.0-1~exp2 (37 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
ocaml4.13.1-4 ... 5.5.0-1~exp2 (32 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
ocaml5.3.0-3 ... 5.5.0-1~exp2 (11 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
ocaml5.3.0-3 ... 5.4.1-1~exp1 (8 versions)5.4.1-1—

Weakness Classification(2)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 7× in last 7d / 57× 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 106 total refreshes for this CVE.

  1. 2026-08-25 13:49 UTCEPSS rescore
  2. 2026-08-24 14:17 UTCEPSS rescore
  3. 2026-08-23 00:19 UTCEPSS rescore
  4. 2026-08-21 23:49 UTCEPSS rescore
  5. 2026-08-20 22:55 UTCEPSS rescore
  6. 2026-08-20 22:55 UTCEPSS rescore
  7. 2026-08-19 17:03 UTCEPSS rescore
  8. 2026-08-18 13:48 UTCEPSS rescore
  9. 2026-08-17 13:47 UTCEPSS rescore
  10. 2026-08-16 14:56 UTCEPSS rescore
  11. 2026-08-16 02:14 UTCEPSS rescore
  12. 2026-08-15 01:30 UTCEPSS rescore
  13. 2026-08-14 21:08 UTCVendor advisory
  14. 2026-08-14 21:08 UTCGHSA enrichment
  15. 2026-08-14 08:50 UTCEG score recompute
  16. 2026-08-14 08:50 UTCGHSA enrichment
  17. 2026-08-13 22:00 UTCEPSS rescore
  18. 2026-08-13 00:48 UTCEG score recompute
  19. 2026-08-13 00:48 UTCGHSA enrichment
  20. 2026-08-12 13:50 UTCEPSS rescore
  21. 2026-08-11 23:36 UTCEG score recompute
  22. 2026-08-11 23:36 UTCVendor advisory
  23. 2026-08-11 23:36 UTCGHSA enrichment
  24. 2026-08-11 13:42 UTCEPSS rescore
  25. 2026-08-11 06:10 UTCEG score recompute
Show 75 more
  1. 2026-08-11 06:10 UTCVendor advisory
  2. 2026-08-11 06:10 UTCGHSA enrichment
  3. 2026-08-11 00:00 UTCEPSS rescore
  4. 2026-08-10 08:30 UTCVendor advisory
  5. 2026-08-10 08:30 UTCGHSA enrichment
  6. 2026-08-09 19:59 UTCEG score recompute
  7. 2026-08-09 19:59 UTCVendor advisory
  8. 2026-08-09 19:59 UTCGHSA enrichment
  9. 2026-08-09 13:46 UTCEPSS rescore
  10. 2026-08-09 08:29 UTCEG score recompute
  11. 2026-08-09 08:29 UTCGHSA enrichment
  12. 2026-08-08 16:37 UTCEPSS rescore
  13. 2026-08-08 07:59 UTCGHSA enrichment
  14. 2026-08-07 20:29 UTCEG score recompute
  15. 2026-08-07 20:29 UTCGHSA enrichment
  16. 2026-08-06 13:46 UTCEPSS rescore
  17. 2026-08-06 02:55 UTCEG score recompute
  18. 2026-08-06 02:55 UTCVendor advisory
  19. 2026-08-06 02:55 UTCGHSA enrichment
  20. 2026-08-05 19:17 UTCEPSS rescore
  21. 2026-08-04 15:10 UTCEPSS rescore
  22. 2026-08-04 04:54 UTCEG score recompute
  23. 2026-08-04 04:54 UTCGHSA enrichment
  24. 2026-08-03 10:36 UTCEPSS rescore
  25. 2026-08-02 19:23 UTCEG score recompute
  26. 2026-08-02 19:23 UTCVendor advisory
  27. 2026-08-02 19:23 UTCGHSA enrichment
  28. 2026-08-02 02:26 UTCEPSS rescore
  29. 2026-08-01 04:16 UTCEPSS rescore
  30. 2026-07-30 16:27 UTCEPSS rescore
  31. 2026-07-30 01:30 UTCEPSS rescore
  32. 2026-07-28 15:36 UTCEPSS rescore
  33. 2026-07-26 14:54 UTCEPSS rescore
  34. 2026-07-26 14:54 UTCEPSS rescore
  35. 2026-07-25 14:18 UTCEPSS rescore
  36. 2026-07-25 14:17 UTCEPSS rescore
  37. 2026-07-24 14:17 UTCEPSS rescore
  38. 2026-07-23 14:18 UTCEPSS rescore
  39. 2026-07-23 14:18 UTCEPSS rescore
  40. 2026-07-23 03:08 UTCEG score recompute
  41. 2026-07-22 14:08 UTCEPSS rescore
  42. 2026-07-22 14:08 UTCEPSS rescore
  43. 2026-07-21 15:24 UTCEPSS rescore
  44. 2026-07-21 15:24 UTCEPSS rescore
  45. 2026-07-20 17:08 UTCEPSS rescore
  46. 2026-07-20 17:08 UTCEPSS rescore
  47. 2026-07-19 14:31 UTCEPSS rescore
  48. 2026-07-19 14:31 UTCEPSS rescore
  49. 2026-07-19 02:29 UTCEPSS rescore
  50. 2026-07-18 10:04 UTCEPSS rescore
  51. 2026-07-18 10:04 UTCEPSS rescore
  52. 2026-07-18 06:59 UTCOSV refresh
  53. 2026-07-16 17:03 UTCEPSS rescore
  54. 2026-07-16 17:03 UTCEPSS rescore
  55. 2026-07-15 16:57 UTCEPSS rescore
  56. 2026-07-15 16:57 UTCEPSS rescore
  57. 2026-07-15 02:22 UTCNVD updateCVSS v3 → 7.8
  58. 2026-07-15 02:00 UTCEPSS rescore
  59. 2026-07-15 02:00 UTCEPSS rescore
  60. 2026-07-15 01:21 UTCMITRE cvelistV5CVSS v3 → 7.9
  61. 2026-07-13 22:30 UTCEPSS rescore
  62. 2026-07-13 06:13 UTCEPSS rescore
  63. 2026-07-13 06:13 UTCEPSS rescore
  64. 2026-07-12 05:46 UTCEPSS rescore
  65. 2026-07-11 08:27 UTCEPSS rescore
  66. 2026-07-09 19:10 UTCEPSS rescore
  67. 2026-07-08 15:15 UTCEPSS rescore
  68. 2026-07-07 13:46 UTCEPSS rescore
  69. 2026-07-06 16:27 UTCEPSS rescore
  70. 2026-07-06 16:27 UTCEPSS rescore
  71. 2026-07-06 02:23 UTCEPSS rescore
  72. 2026-07-06 02:23 UTCEPSS rescore
  73. 2026-07-05 02:30 UTCEPSS rescore
  74. 2026-07-04 06:31 UTCEPSS rescore
  75. 2026-07-01 15:06 UTCEPSS rescore

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-28364?
CVE-2026-28364 is a high vulnerability published on February 27, 2026. In OCaml before 4.14.3 and 5.x before 5.4.1, a buffer over-read in Marshal deserialization (runtime/intern.c) enables remote code execution through a multi-phase attack chain. The vulnerability stems from missing bounds validation in the readblock() function, which performs unbounded memcpy()…
When was CVE-2026-28364 disclosed?
CVE-2026-28364 was first published in the National Vulnerability Database on February 27, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-28364 actively exploited?
CVE-2026-28364 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 88.9% of all scored CVEs.
What is the CVSS score of CVE-2026-28364?
CVE-2026-28364 has a CVSS v3 base score of 7.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 7.9.
How do I remediate CVE-2026-28364?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-28364, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-28364

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