PYSEC-2026-2293

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Import Source

https://github.com/pypa/advisory-database/blob/main/vulns/ujson/PYSEC-2026-2293.yaml

JSON Data

https://api.osv.dev/v1/vulns/PYSEC-2026-2293

Aliases

Published

2026-05-27T21:16:17.650Z

Modified

2026-07-13T07:15:45.423783162Z

Severity

7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator

Summary

[none]

Details

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.

References

Affected packages

PyPI / ujson

Package

Name: ujson; View open source insights on deps.dev
Purl: pkg:pypi/ujson

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

5.12.1

Affected versions

1.*

1.4

1.6

1.8

1.9

1.15

1.18

1.19

1.21

1.22

1.23

1.30

1.33

1.34

1.35

2.*

2.0.0

2.0.1

2.0.2

2.0.3

3.*

3.0.0

3.1.0

3.2.0

4.*

4.0.0

4.0.1

4.0.2

4.1.0

4.2.0

4.3.0

5.*

5.0.0

5.1.0

5.2.0

5.3.0

5.4.0

5.5.0

5.6.0

5.7.0

5.8.0

5.9.0

5.10.0

5.11.0

5.12.0

Database specific

source

"https://github.com/pypa/advisory-database/blob/main/vulns/ujson/PYSEC-2026-2293.yaml"