MEDIUM6.5
PYSEC-2026-2294
Quick fix
PYSEC-2026-2294 — ujson: upgrade to the fixed version with the command below.
pip install --upgrade 'ujson>=5.13.0'Details
UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. Prior to 5.13.0, ujson.dumps() (or ujson.dump() or ujson.encode()) have a reject_bytes=False option. When set, they may accept malformed or truncated UTF-8 byte sequences, silently rewriting them into different Unicode characters instead of rejecting them. This leads to input validation bypass and data integrity issues. This vulnerability is fixed in 5.13.0.
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