{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.6.5"
              }
            ],
            "source": [
              "DESCRIPTION",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5102eddff28d9b605f3e6783d50ad380f61f692e"
            },
            {
              "fixed": "22b9afc800c5833f9e851e35938972bd4c76a357"
            }
          ],
          "repo": "https://github.com/michaelrsweet/pdfio",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-825"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77220.json"
  },
  "details": "PDFio before 1.6.5 contains a dangling pointer vulnerability in the dictionary string-formatting function that stores a pointer to a stack-local buffer in the document dictionary without copying the string value. In multi-threaded or pooled-request environments, attackers or concurrent users can trigger stack memory reuse across requests, causing cross-tenant document content corruption by silently overwriting one caller's dictionary string values with another caller's data.",
  "id": "CVE-2026-77220",
  "modified": "2026-08-27T11:30:32.756937303Z",
  "published": "2026-08-21T20:54:34.762Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77220.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/michaelrsweet/pdfio/releases/tag/v1.6.5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77220"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/pdfio-dangling-pointer-via-dictionary-string-formatting"
    },
    {
      "type": "FIX",
      "url": "https://github.com/michaelrsweet/pdfio/commit/22b9afc800c5833f9e851e35938972bd4c76a357"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/michaelrsweet/pdfio"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "PDFio \u003c 1.6.5 Dangling Pointer via Dictionary String-Formatting"
}