VULNERABILITY INTELLIGENCE
CVE-2026-44660
CVSS score7.5 HIGH
EPSS probability0.42%
CISA KEVNot currently listed
Published2026-05-27
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Description
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.
Weakness classification
- security-advisories@github.com: CWE-401
Primary references
- security-advisories@github.com — Patch
- security-advisories@github.com — Product, Release Notes
- security-advisories@github.com — Exploit, Mitigation, Patch, Vendor Advisory
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 — Exploit, Mitigation, Patch, Vendor Advisory