DEBIAN-CVE-2026-32874
UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. Versions 5.4.0 through 5.11.0 contain an accumulating memory leak in JSON parsing large (outside of the range [-2^63, 2^64 - 1]) integers. The leaked memory is a copy of the string form of the integer plus an additional NULL byte. The leak occurs irrespective of whether the integer parses successfully or is rejected due to having more than sys.get_int_max_str_digits() digits, meaning that any sized leak per malicious JSON can be achieved provided that there is no limit on the overall size of the payload. Any service that calls ujson.load()/ujson.loads()/ujson.decode() on untrusted inputs is affected and vulnerable to denial of service attacks. This issue has been fixed in version 5.12.0.
DEBIAN-CVE-2026-32874
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-32874
ujson
Source reference: /affected/0/package/name
- Affected versions
- 5.10.0-1
Source reference:
/affected/0/versions5.11.0-1Source reference:
/affected/0/versions5.11.0-2Source reference:
/affected/0/versions5.11.0-3Source reference:
/affected/0/versions5.13.0-1Source reference:
/affected/0/versions5.7.0-1Source reference:
/affected/0/versions5.8.0-1Source reference:
/affected/0/versions5.9.0-1Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
ujson
Source reference: /affected/1/package/name
- Affected versions
- 5.10.0-1
Source reference:
/affected/1/versions5.11.0-1Source reference:
/affected/1/versions5.11.0-2Source reference:
/affected/1/versions5.11.0-3Source reference:
/affected/1/versions5.13.0-1Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
ujson
Source reference: /affected/2/package/name
- Affected versions
- 5.10.0-1
Source reference:
/affected/2/versions5.11.0-1Source reference:
/affected/2/versions5.11.0-2Source reference:
/affected/2/versions5.11.0-3Source reference:
/affected/2/versions - Fixed versions
- 5.13.0-1
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "ujson",
"purl": "pkg:deb/debian/ujson?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"5.10.0-1",
"5.11.0-1",
"5.11.0-2",
"5.11.0-3",
"5.13.0-1",
"5.7.0-1",
"5.8.0-1",
"5.9.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-32874.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "ujson",
"purl": "pkg:deb/debian/ujson?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"5.10.0-1",
"5.11.0-1",
"5.11.0-2",
"5.11.0-3",
"5.13.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-32874.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "5.13.0-1"
}
]
}
],
"package": {
"name": "ujson",
"purl": "pkg:deb/debian/ujson?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"5.10.0-1",
"5.11.0-1",
"5.11.0-2",
"5.11.0-3"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-32874.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #56787 · Revision 1
- Added to Heist Feed
- Publisher date