{"schema_version":1,"title":"ujson (PyPI) vulnerabilities","summary":"Junglewise Threat Intelligence has tracked 9 vulnerabilities in ujson (PyPI): 0 in the last 7 days and 2 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.","url":"https://junglewise.ai/threats/technologies/ujson","json_url":"https://junglewise.ai/threats/technologies/ujson.json","publisher":"Junglewise Threat Intelligence","license":"CC-BY-4.0","license_url":"https://creativecommons.org/licenses/by/4.0/","attribution":"Junglewise Threat Intelligence, https://junglewise.ai/threats/technologies/ujson","sources":"NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories","kind":"technology","counts":{"high":3,"all_time":9,"critical":0,"exploited":0,"last_7_days":0,"last_30_days":0,"last_90_days":2,"last_365_days":6},"latest":[{"cve":"CVE-2022-31116","cvss":3.1,"epss":0.0262,"slug":"cve-2022-31116-incorrect-handling-of-invalid-surrogate-pair-characters","title":"PYSEC-2026-1057 - Incorrect handling of invalid surrogate pair characters","severity":"low","exploited":false,"published_at":"2026-07-06T08:03:31.058927+00:00","url":"https://junglewise.ai/threats/cve-2022-31116-incorrect-handling-of-invalid-surrogate-pair-characters"},{"cve":"CVE-2022-31117","cvss":3.1,"epss":0.0188,"slug":"cve-2022-31117-potential-double-free-of-buffer-during-string-decoding","title":"PYSEC-2026-1056 - Potential double free of buffer during string decoding","severity":"low","exploited":false,"published_at":"2026-07-06T08:03:30.989917+00:00","url":"https://junglewise.ai/threats/cve-2022-31117-potential-double-free-of-buffer-during-string-decoding"},{"cve":"CVE-2026-54911","cvss":6.5,"epss":0.0037,"slug":"cve-2026-54911-ultrajson-improper-input-validation-in-ujson-dumps-utf-8-handling","title":"UltraJSON improper input validation in ujson.dumps UTF-8 handling","severity":"medium","exploited":false,"published_at":"2026-06-22T22:16:50.397+00:00","url":"https://junglewise.ai/threats/cve-2026-54911-ultrajson-improper-input-validation-in-ujson-dumps-utf-8-handling"},{"cve":"CVE-2026-44660","cvss":7.5,"epss":0.0064,"slug":"cve-2026-44660-ultrajson-memory-leak-in-ujson-dump-on-write-failure","title":"UltraJSON memory leak in ujson.dump on write failure","severity":"high","exploited":false,"published_at":"2026-05-27T21:16:17.65+00:00","url":"https://junglewise.ai/threats/cve-2026-44660-ultrajson-memory-leak-in-ujson-dump-on-write-failure"},{"cve":"CVE-2026-32875","cvss":7.5,"epss":0.0077,"slug":"cve-2026-32875-ultrajson-integer-overflow-in-indent-handling","title":"UltraJSON integer overflow in indent handling","severity":"high","exploited":false,"published_at":"2026-03-20T02:16:35.887+00:00","url":"https://junglewise.ai/threats/cve-2026-32875-ultrajson-integer-overflow-in-indent-handling"},{"cve":"CVE-2026-32874","cvss":7.5,"epss":0.0068,"slug":"cve-2026-32874-ultrajson-memory-leak-in-json-parsing-of-large-integers","title":"UltraJSON memory leak in JSON parsing of large integers","severity":"high","exploited":false,"published_at":"2026-03-20T02:16:35.703+00:00","url":"https://junglewise.ai/threats/cve-2026-32874-ultrajson-memory-leak-in-json-parsing-of-large-integers"},{"slug":"osv-2021-1809-heap-buffer-overflow-in-ujson-cpython-38-x86-64-linux-gnu-0780b9df","title":"OSV-2021-1809 - Heap-buffer-overflow in ujson.cpython-38-x86_64-linux-gnu.so","severity":"info","exploited":false,"published_at":"2022-02-25T00:00:25.106722+00:00","url":"https://junglewise.ai/threats/osv-2021-1809-heap-buffer-overflow-in-ujson-cpython-38-x86-64-linux-gnu-0780b9df"},{"cve":"CVE-2021-45958","cvss":3.1,"epss":0.0155,"slug":"cve-2021-45958-ultrajson-vulnerable-to-out-of-bounds-write","title":"PYSEC-2022-25 - UltraJSON (aka ujson) through 5.1.0 has a stack-based buffer overflow in Buffer_AppendIndentUnchecked (called from encode). Exploitation can","severity":"low","exploited":false,"published_at":"2022-01-01T00:15:00+00:00","url":"https://junglewise.ai/threats/cve-2021-45958-ultrajson-vulnerable-to-out-of-bounds-write"},{"slug":"osv-2021-955-stack-buffer-overflow-in-buffer-appendindentunchecked-c5a59190","title":"OSV-2021-955 - Stack-buffer-overflow in Buffer_AppendIndentUnchecked","severity":"info","exploited":false,"published_at":"2021-07-11T00:01:05.153778+00:00","url":"https://junglewise.ai/threats/osv-2021-955-stack-buffer-overflow-in-buffer-appendindentunchecked-c5a59190"}],"weekly":[{"week":"2026-07-06","critical":0,"exploited":0,"vulnerabilities":2},{"week":"2026-07-13","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-20","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-27","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-03","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-10","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-17","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-24","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-31","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-07","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-14","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-21","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-28","critical":0,"exploited":0,"vulnerabilities":0}],"related":[{"name":"tensorflow (PyPI)","slug":"pypi-tensorflow","vulnerabilities":428,"url":"https://junglewise.ai/threats/technologies/pypi-tensorflow"},{"name":"tensorflow-cpu (PyPI)","slug":"tensorflow-cpu","vulnerabilities":424,"url":"https://junglewise.ai/threats/technologies/tensorflow-cpu"},{"name":"tensorflow-gpu (PyPI)","slug":"tensorflow-gpu","vulnerabilities":421,"url":"https://junglewise.ai/threats/technologies/tensorflow-gpu"},{"name":"open-webui (PyPI)","slug":"open-webui","vulnerabilities":177,"url":"https://junglewise.ai/threats/technologies/open-webui"},{"name":"Django (PyPI)","slug":"django","vulnerabilities":172,"url":"https://junglewise.ai/threats/technologies/django"},{"name":"apache-airflow (PyPI)","slug":"apache-airflow","vulnerabilities":152,"url":"https://junglewise.ai/threats/technologies/apache-airflow"},{"name":"plone (PyPI)","slug":"pypi-plone","vulnerabilities":101,"url":"https://junglewise.ai/threats/technologies/pypi-plone"},{"name":"praisonai (PyPI)","slug":"pypi-praisonai","vulnerabilities":86,"url":"https://junglewise.ai/threats/technologies/pypi-praisonai"},{"name":"exiv2 (PyPI)","slug":"exiv2","vulnerabilities":85,"url":"https://junglewise.ai/threats/technologies/exiv2"},{"name":"nltk (PyPI)","slug":"nltk","vulnerabilities":83,"url":"https://junglewise.ai/threats/technologies/nltk"},{"name":"mlflow (PyPI)","slug":"mlflow","vulnerabilities":82,"url":"https://junglewise.ai/threats/technologies/mlflow"},{"name":"pillow (PyPI)","slug":"pillow","vulnerabilities":79,"url":"https://junglewise.ai/threats/technologies/pillow"}],"technology":{"hub":true,"name":"ujson (PyPI)","slug":"ujson","vendor":{"name":"PyPI","slug":"pypi","url":"https://junglewise.ai/threats/vendors/pypi"},"aliases":[],"homepage":"https://pypi.org/project/ujson/","repo_url":"https://github.com/ultrajson/ultrajson","description":"UltraJSON is an ultra fast JSON encoder and decoder written in C with bindings for Python.","url":"https://junglewise.ai/threats/technologies/ujson"},"most_severe":[{"cve":"CVE-2026-32875","cvss":7.5,"epss":0.0077,"slug":"cve-2026-32875-ultrajson-integer-overflow-in-indent-handling","title":"UltraJSON integer overflow in indent handling","severity":"high","exploited":false,"published_at":"2026-03-20T02:16:35.887+00:00","url":"https://junglewise.ai/threats/cve-2026-32875-ultrajson-integer-overflow-in-indent-handling"},{"cve":"CVE-2026-32874","cvss":7.5,"epss":0.0068,"slug":"cve-2026-32874-ultrajson-memory-leak-in-json-parsing-of-large-integers","title":"UltraJSON memory leak in JSON parsing of large integers","severity":"high","exploited":false,"published_at":"2026-03-20T02:16:35.703+00:00","url":"https://junglewise.ai/threats/cve-2026-32874-ultrajson-memory-leak-in-json-parsing-of-large-integers"},{"cve":"CVE-2026-44660","cvss":7.5,"epss":0.0064,"slug":"cve-2026-44660-ultrajson-memory-leak-in-ujson-dump-on-write-failure","title":"UltraJSON memory leak in ujson.dump on write failure","severity":"high","exploited":false,"published_at":"2026-05-27T21:16:17.65+00:00","url":"https://junglewise.ai/threats/cve-2026-44660-ultrajson-memory-leak-in-ujson-dump-on-write-failure"},{"cve":"CVE-2026-54911","cvss":6.5,"epss":0.0037,"slug":"cve-2026-54911-ultrajson-improper-input-validation-in-ujson-dumps-utf-8-handling","title":"UltraJSON improper input validation in ujson.dumps UTF-8 handling","severity":"medium","exploited":false,"published_at":"2026-06-22T22:16:50.397+00:00","url":"https://junglewise.ai/threats/cve-2026-54911-ultrajson-improper-input-validation-in-ujson-dumps-utf-8-handling"},{"cve":"CVE-2022-31116","cvss":3.1,"epss":0.0262,"slug":"cve-2022-31116-incorrect-handling-of-invalid-surrogate-pair-characters","title":"PYSEC-2026-1057 - Incorrect handling of invalid surrogate pair characters","severity":"low","exploited":false,"published_at":"2026-07-06T08:03:31.058927+00:00","url":"https://junglewise.ai/threats/cve-2022-31116-incorrect-handling-of-invalid-surrogate-pair-characters"},{"cve":"CVE-2022-31117","cvss":3.1,"epss":0.0188,"slug":"cve-2022-31117-potential-double-free-of-buffer-during-string-decoding","title":"PYSEC-2026-1056 - Potential double free of buffer during string decoding","severity":"low","exploited":false,"published_at":"2026-07-06T08:03:30.989917+00:00","url":"https://junglewise.ai/threats/cve-2022-31117-potential-double-free-of-buffer-during-string-decoding"},{"cve":"CVE-2021-45958","cvss":3.1,"epss":0.0155,"slug":"cve-2021-45958-ultrajson-vulnerable-to-out-of-bounds-write","title":"PYSEC-2022-25 - UltraJSON (aka ujson) through 5.1.0 has a stack-based buffer overflow in Buffer_AppendIndentUnchecked (called from encode). Exploitation can","severity":"low","exploited":false,"published_at":"2022-01-01T00:15:00+00:00","url":"https://junglewise.ai/threats/cve-2021-45958-ultrajson-vulnerable-to-out-of-bounds-write"},{"slug":"osv-2021-1809-heap-buffer-overflow-in-ujson-cpython-38-x86-64-linux-gnu-0780b9df","title":"OSV-2021-1809 - Heap-buffer-overflow in ujson.cpython-38-x86_64-linux-gnu.so","severity":"info","exploited":false,"published_at":"2022-02-25T00:00:25.106722+00:00","url":"https://junglewise.ai/threats/osv-2021-1809-heap-buffer-overflow-in-ujson-cpython-38-x86-64-linux-gnu-0780b9df"},{"slug":"osv-2021-955-stack-buffer-overflow-in-buffer-appendindentunchecked-c5a59190","title":"OSV-2021-955 - Stack-buffer-overflow in Buffer_AppendIndentUnchecked","severity":"info","exploited":false,"published_at":"2021-07-11T00:01:05.153778+00:00","url":"https://junglewise.ai/threats/osv-2021-955-stack-buffer-overflow-in-buffer-appendindentunchecked-c5a59190"}],"generated_at":"2026-09-28T03:07:00.154823+00:00"}