CVE-2022-31116

Public Exploit
Incorrect handling of invalid surrogate pair characters in ujson

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.04%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: ultrajson ultrajson
Published at:
Updated at:

References

Link Tags
https://github.com/ultrajson/ultrajson/security/advisories/GHSA-wpqr-jcpx-745r third party advisory exploit
https://github.com/ultrajson/ultrajson/commit/67ec07183342589d602e0fcf7bb1ff3e19272687 third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPPU5FZP3LCTXYORFH7NHUMYA5X66IA7/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NAU5N4A7EUK2AMUCOLYDD5ARXAJYZBD2/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2022-31116?
CVE-2022-31116 has been scored as a high severity vulnerability.
How to fix CVE-2022-31116?
To fix CVE-2022-31116, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2022-31116 being actively exploited in the wild?
It is possible that CVE-2022-31116 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-31116?
CVE-2022-31116 affects ultrajson ultrajson.
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