CVE-2026-44660 (GCVE-0-2026-44660)

Vulnerability from cvelistv5 – Published: 2026-05-27 20:42 – Updated: 2026-05-30 01:49
VLAI
Title
UltraJSON: Memory Leak in ujson.dump() on Write Failure
Summary
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.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-30 01:49 UTC
CWE
  • CWE-401 - Missing Release of Memory after Effective Lifetime
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
ultrajson ultrajson Affected: < 5.12.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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