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BREW-PYTHON-LSP-SERVER-C… (GHSA-FH56-85CW-5PQ6)

Vulnerability from osv_homebrew – Published: 2026-08-13 17:29 – Updated: 2026-09-10 01:01 – Source website
VLAI
Summary
UltraJSON vulnerable to Out-of-bounds Write
Details

UltraJSON (aka ujson) 1.34 through 5.1.0 has a stack-based buffer overflow in Buffer_AppendIndentUnchecked (called from encode).

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
6.8 (Medium)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "resource": "ujson",
        "resource_purl": "pkg:pypi/ujson@5.13.0",
        "upstream_fixed_in": "5.2.0"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "python-lsp-server",
        "purl": "pkg:brew/python-lsp-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.15.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/ujson@5.13.0",
        "name": "ujson",
        "resource": "ujson",
        "strategy": "registry",
        "subject_version": "5.13.0"
      }
    ]
  },
  "details": "UltraJSON (aka ujson) 1.34 through 5.1.0 has a stack-based buffer overflow in Buffer_AppendIndentUnchecked (called from encode).",
  "id": "BREW-python-lsp-server-CVE-2021-45958",
  "modified": "2026-09-10T01:01:31Z",
  "published": "2026-08-13T17:29:47Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-45958"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ultrajson/ultrajson/issues/501"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ultrajson/ultrajson/issues/502#issuecomment-1031747284"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ultrajson/ultrajson/pull/504"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ultrajson/ultrajson/pull/519"
    },
    {
      "type": "WEB",
      "url": "https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=36009"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-fh56-85cw-5pq6"
    },
    {
      "type": "WEB",
      "url": "https://github.com/google/oss-fuzz-vulns/blob/main/vulns/ujson/OSV-2021-955.yaml"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/ujson/PYSEC-2022-25.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ultrajson/ultrajson"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2022/02/msg00023.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CN7W3GOXALINKFUUE7ICQIC2EF5HNKUQ"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NAU5N4A7EUK2AMUCOLYDD5ARXAJYZBD2"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/O6JUWQTJLA2CMG4CJN7DCUVSOXLZIIXL"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ULX35TSWLBBIMEH44MUORPXYYRZKEDC6"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "UltraJSON vulnerable to Out-of-bounds Write",
  "upstream": [
    "GHSA-fh56-85cw-5pq6",
    "CVE-2021-45958",
    "PYSEC-2022-25"
  ]
}



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