CVE-2026-54911 (GCVE-0-2026-54911)
Vulnerability from cvelistv5
Published
2026-06-22 20:53
Modified
2026-06-23 14:20
CWE
  • CWE-20 - Improper Input Validation
Summary
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.
Impacted products
Vendor Product Version
ultrajson ultrajson Version: < 5.13.0
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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