Skip to content
Heist/ feed
UnratedFix available

DEBIAN-CVE-2026-32875

Type: advisorySource: OSV1 source record

UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. Versions 5.10 through 5.11.0 are vulnerable to buffer overflow or infinite loop through large indent handling. ujson.dumps() crashes the Python interpreter (segmentation fault) when the product of the indent parameter and the nested depth of the input exceeds INT32_MAX. It can also get stuck in an infinite loop if the indent is a large negative number. Both are caused by an integer overflow/underflow whilst calculating how much memory to reserve for indentation. And both can be used to achieve denial of service. To be vulnerable, a service must call ujson.dump()/ujson.dumps()/ujson.encode() whilst giving untrusted users control over the indent parameter and not restrict that indentation to reasonably small non-negative values. A service may also be vulnerable to the infinite loop if it uses a fixed negative indent. An underflow always occurs for any negative indent when the input data is at least one level nested but, for small negative indents, the underflow is usually accidentally rectified by another overflow. This issue has been fixed in version 5.12.0.

Announced Source revision 1
Original source ↗

DEBIAN-CVE-2026-32875

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-2026-32875

ujson

Source reference: /affected/0/package/name

Affected versions
5.10.0-1

Source reference: /affected/0/versions

5.11.0-1

Source reference: /affected/0/versions

5.11.0-2

Source reference: /affected/0/versions

5.11.0-3

Source reference: /affected/0/versions

5.13.0-1

Source reference: /affected/0/versions

5.7.0-1

Source reference: /affected/0/versions

5.8.0-1

Source reference: /affected/0/versions

5.9.0-1

Source 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/versions

5.11.0-1

Source reference: /affected/1/versions

5.11.0-2

Source reference: /affected/1/versions

5.11.0-3

Source reference: /affected/1/versions

5.13.0-1

Source 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/versions

5.11.0-1

Source reference: /affected/2/versions

5.11.0-2

Source reference: /affected/2/versions

5.11.0-3

Source 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-2026-32875.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-2026-32875.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-2026-32875.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  }
]

Publisher severity

No explicit severity was provided.

Event
#57519 · Revision 1
Added to Heist Feed
Publisher date
Read the original announcement