Technology · PyPI
ujson (PyPI) vulnerabilities
Updated . Rebuilt every hour.
Junglewise Threat Intelligence has tracked 9 vulnerabilities in ujson (PyPI): 0 in the last 7 days and 0 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2022-31116, was published on 6 July 2026.
- Last 7 days
- 0
- Last 90 days
- 0
- Critical, all time
- 0
- Exploited in the wild
- 0
About ujson (PyPI)
ujson is a Python library for fast JSON encoding and decoding.
Latest ujson (PyPI) vulnerabilities
- CVE-2022-31116: PYSEC-2026-1057 - Incorrect handling of invalid surrogate pair characterslowCVSS 3.1EPSS 2.6%
- CVE-2022-31117: PYSEC-2026-1056 - Potential double free of buffer during string decodinglowCVSS 3.1EPSS 1.9%
- CVE-2026-54911: UltraJSON improper input validation in ujson.dumps UTF-8 handlingmediumCVSS 6.5EPSS 0.4%
- CVE-2026-44660: UltraJSON memory leak in ujson.dump on write failurehighCVSS 7.5EPSS 0.6%
- CVE-2026-32875: UltraJSON integer overflow in indent handlinghighCVSS 7.5EPSS 0.8%
- CVE-2026-32874: UltraJSON memory leak in JSON parsing of large integershighCVSS 7.5EPSS 0.7%
- OSV-2021-1809 - Heap-buffer-overflow in ujson.cpython-38-x86_64-linux-gnu.soinfo
- CVE-2021-45958: UltraJSON vulnerable to Out-of-bounds WritelowCVSS 3.1EPSS 1.6%
- OSV-2021-955 - Stack-buffer-overflow in Buffer_AppendIndentUncheckedinfo
Most severe ujson (PyPI) vulnerabilities
Exploited in the wild first, then by severity and CVSS score.
- CVE-2026-32875: UltraJSON integer overflow in indent handlinghighCVSS 7.5EPSS 0.8%
- CVE-2026-32874: UltraJSON memory leak in JSON parsing of large integershighCVSS 7.5EPSS 0.7%
- CVE-2026-44660: UltraJSON memory leak in ujson.dump on write failurehighCVSS 7.5EPSS 0.6%
- CVE-2026-54911: UltraJSON improper input validation in ujson.dumps UTF-8 handlingmediumCVSS 6.5EPSS 0.4%
- CVE-2022-31116: PYSEC-2026-1057 - Incorrect handling of invalid surrogate pair characterslowCVSS 3.1EPSS 2.6%
- CVE-2022-31117: PYSEC-2026-1056 - Potential double free of buffer during string decodinglowCVSS 3.1EPSS 1.9%
- CVE-2021-45958: UltraJSON vulnerable to Out-of-bounds WritelowCVSS 3.1EPSS 1.6%
- OSV-2021-1809 - Heap-buffer-overflow in ujson.cpython-38-x86_64-linux-gnu.soinfo
- OSV-2021-955 - Stack-buffer-overflow in Buffer_AppendIndentUncheckedinfo
Vulnerabilities per week
Nothing was published in the last eight weeks. The last 13 weeks, by the week each vulnerability was published.
| Week of | Bar | Vulns | Critical |
|---|---|---|---|
| 17 Aug 2026 | 0 | 0 | |
| 24 Aug 2026 | 0 | 0 | |
| 31 Aug 2026 | 0 | 0 | |
| 7 Sep 2026 | 0 | 0 | |
| 14 Sep 2026 | 0 | 0 | |
| 21 Sep 2026 | 0 | 0 | |
| 28 Sep 2026 | 0 | 0 | |
| 5 Oct 2026 | 0 | 0 | |
| 12 Oct 2026 | 0 | 0 | |
| 19 Oct 2026 | 0 | 0 | |
| 26 Oct 2026 | 0 | 0 | |
| 2 Nov 2026 | 0 | 0 | |
| 9 Nov 2026 | 0 | 0 |
Embed a badge
A live badge for a README, a status page or an internal wiki: how many ujson (PyPI) vulnerabilities were published in the last 7 days and how many of them are critical, refreshed hourly.
[](https://junglewise.ai/threats/technologies/ujson)<a href="https://junglewise.ai/threats/technologies/ujson"><img src="https://junglewise.ai/threats/technologies/ujson/badge.svg" alt="ujson (PyPI) vulnerabilities" /></a>How this is built
Junglewise Threat Intelligence collects vulnerabilities from NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories, and matches each one to the technologies and vendors it affects. Dates are the date a vulnerability was published, in UTC.
The pages are rebuilt from the database every hour. Frozen weekly and monthly reports never change once published, so they can be cited.
Use this data
The same data is at https://junglewise.ai/threats/technologies/ujson.json, and this page as text at https://junglewise.ai/threats/technologies/ujson.md, for scripts and language models. It is free to reuse under CC BY 4.0 with a link back to this page.
Cite as: Junglewise Threat Intelligence, "ujson (PyPI) vulnerabilities", https://junglewise.ai/threats/technologies/ujson, 13 November 2026.