CVE-2026-44660 (GCVE-0-2026-44660)
Vulnerability from cvelistv5
Published
2026-05-27 20:42
Modified
2026-05-30 01:49
CWE
  • CWE-401 - Missing Release of Memory after Effective Lifetime
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.
Impacted products
Vendor Product Version
ultrajson ultrajson Version: < 5.12.1
Create a notification for this product.
Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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