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Package · Debian

ujson

7 known vulnerabilities.

All Critical High Medium Low Exploited only Public exploit

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  • Medium 6.5
    CVE-2026-54911

    UltraJSON: Malformed/Truncated UTF-8 Accepted and Silently Rewritten in ujson.dumps()

    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 sequ…

    ultrajson ultrajson ujson ujson Debian Ubuntu PyPI
  • Medium 5.9
    CVE-2022-31117

    Double free of buffer during string decoding in ujson

    UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. In versions prior to 5.4.0 an error occurring while reallocating a buffer for string decoding can cause the buffer to get freed twice. Due to how UltraJSON uses the …

    ultrajson ultrajson ujson ujson Debian Ubuntu Alpine PyPI
  • Medium 5.5
    CVE-2021-45958

    UltraJSON vulnerable to Out-of-bounds Write

    UltraJSON (aka ujson) through 5.1.0 has a stack-based buffer overflow in Buffer_AppendIndentUnchecked (called from encode). Exploitation can, for example, use a large amount of indentation.

    ujson ujson ujson py3-ujson Debian Ubuntu Alpine PyPI