CVE-2026-44660

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.4%, top 65% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Elevated
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%CVSS: 7.5Exploit: Elevated riskExposed: 0

A fix is available — apply it.

UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. Prior to 5.12.1, when ujson.dump() writes to a file-like object and the write operation raises an exception, the serialized JSON string object is not decremented, leaking memory. Each failed write operation leaks the full size of the serialized payload. This vulnerability is fixed in 5.12.1.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
65(Attend)
EG Risk 65/100SSVC: Attend

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%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
35%
KEV
Not listed

Published

May 27, 2026

Last Modified

June 2, 2026

Advisory Details (3)

Auto-updated Jun 2, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_release.
github Patch Available🟡 PoC Available

Memory Leak in ujson.dump() on Write Failure · Advisory · ultrajson/ultrajson · GitHub

https://github.com/ultrajson/ultrajson/security/advisories/GHSA-c38f-wx89-p2xg
github_release Patch Available

5.12.1

Patch available: ultrajson/ultrajson 5.12.1

https://github.com/ultrajson/ultrajson/releases/tag/5.12.1
github_commit Patch Available

commit 82af1d0ac01d (ultrajson/ultrajson)

Patch available: ultrajson/ultrajson 5.12.1 (contains commit 82af1d0ac01d)

https://github.com/ultrajson/ultrajson/commit/82af1d0ac01d09aa40c887b460d44b9d9f4bccd9

Vendor Advisories for CVE-2026-44660(5)

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

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatsatellite/iop-host-inventory-rhel9:17859706782026-08-06redhat
redhatsatellite/iop-host-inventory-rhel9:17859567302026-08-06redhat
redhatrhoai/odh-llama-stack-core-rhel9:17837015982026-07-21redhat

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

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
ujson4.0.2-1 ... 5.9.0-1 (17 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
ujson5.10.0-1 ... 5.9.0-1 (8 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
ujson5.10.0-1, 5.11.0-1, 5.11.0-2, 5.11.0-3, 5.13.0-1——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
ujson5.10.0-1, 5.11.0-1, 5.11.0-2, 5.11.0-35.13.0-1—
PyPI(1)
PackageVulnerable rangeFixed inDependents
ujson1.15 ... 5.9.0 (40 versions)5.12.1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 4× in last 7d / 59× 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 166 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-44660?
CVE-2026-44660 is a high vulnerability published on May 27, 2026. UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. Prior to 5.12.1, when ujson.dump() writes to a file-like object and the write operation raises an exception, the serialized JSON string object is not decremented, leaking memory. Each failed write…
When was CVE-2026-44660 disclosed?
CVE-2026-44660 was first published in the National Vulnerability Database on May 27, 2026, with the most recent update on June 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-44660 actively exploited?
CVE-2026-44660 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 64.7% of all scored CVEs.
What is the CVSS score of CVE-2026-44660?
CVE-2026-44660 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-44660?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-44660, 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-2026-44660

Explore →

Is Your Infrastructure Affected by CVE-2026-44660?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs