Incorrect handling of invalid surrogate pair characters in ujson (ultrajson ultrajson)
At a glance
- Source
- NVD
- EPSS
- EPSS 2.54 % · percentile 85 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Modified
Description
UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. Affected versions were found to improperly decode certain characters. JSON strings that contain escaped surrogate characters not part of a proper surrogate pair were decoded incorrectly. Besides corrupting strings, this allowed for potential key confusion and value overwriting in dictionaries. All users parsing JSON from untrusted sources are vulnerable. From version 5.4.0, UltraJSON decodes lone surrogates in the same way as the standard library's `json` module does, preserving them in the parsed output. Users are advised to upgrade. There are no known workarounds for this issue.
Weaknesses (CWE)
- CWE-670 — Always-Incorrect Control Flow Implementation
References
- https://github.com/ultrajson/ultrajson/security/advisories/GHSA-wpqr-jcpx-745r
- https://github.com/ultrajson/ultrajson/commit/67ec07183342589d602e0fcf7bb1ff3e19272687
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPPU5FZP3LCTXYORFH7NHUMYA5X66IA7/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NAU5N4A7EUK2AMUCOLYDD5ARXAJYZBD2/
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · security-advisories@github.com (Secondary) |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · nvd@nist.gov (Primary) |
| CVSS 2.0 | MEDIUM 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P | NVD · nvd@nist.gov (Primary) |
Advisories
- GHSA-wpqr-jcpx-745r — Incorrect handling of invalid surrogate pair characters
- PYSEC-2026-1057 — Incorrect handling of invalid surrogate pair characters
European references
- ENISA EUVD · EUVD-2022-6438
- GCVE · GCVE-0-2022-31116
CERT-FR advisories
- CERTFR-2024-AVI-0366 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:ultrajson_project:ultrajson:*:*:*:*:*:python:*:*< 5.4.0cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| ultrajson · ultrajson | affected < 5.4.0 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |