{
  "fix": "libexpat1 2.7.4-1ubuntu0.2",
  "url": "https://patchblox.com/security/fix/linux/ubuntu-resolute-libexpat1-2.7.4-1ubuntu0.2",
  "summary": "libexpat1 2.7.4-1ubuntu0.2, released August 20, 2026, fixes 11 CVEs in libexpat1. None of them is reported as exploited. Patch Radar priority: High.",
  "platform": "linux",
  "type": "package",
  "title": "libexpat1 2.7.4-1ubuntu0.2 for Ubuntu 26.04.1 LTS (resolute)",
  "released": "2026-08-20T11:16:00Z",
  "priority": "High",
  "priorityTier": 3,
  "priorityReason": "Closes CVE-2026-66046, high severity",
  "supported": true,
  "cveCount": 11,
  "exploitedCveCount": 0,
  "kevCveCount": 0,
  "ransomwareCveCount": 0,
  "maxEpss": 0.00862,
  "maxCvss": 7.8,
  "appliesTo": [
    {
      "product": "libexpat1",
      "productUrl": "https://patchblox.com/security/product/linux/libexpat1",
      "release": "Ubuntu 26.04.1 LTS (resolute)",
      "fixedVersion": "2.7.4-1ubuntu0.2",
      "supported": true
    }
  ],
  "cves": [
    {
      "cveId": "CVE-2026-66046",
      "url": "https://patchblox.com/security/cve/CVE-2026-66046",
      "title": "Expat Denial of Service via storeAtts() Quadratic Complexity",
      "priority": "High",
      "severity": "Important",
      "cvss": 7.5,
      "epss": 0.00862,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-76957",
      "url": "https://patchblox.com/security/cve/CVE-2026-76957",
      "title": "libexpat before 2.8.4 lacks handler call depth tracking with custom encoding callbacks. Thus, a use-after-free can occur. NOTE: this is similar to CVE-2026-50219, CVE-2026-56131 and CVE-2026-56412.",
      "priority": "High",
      "severity": "Moderate",
      "cvss": 7.8,
      "epss": 0.00119,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-76641",
      "url": "https://patchblox.com/security/cve/CVE-2026-76641",
      "title": "expat: out-of-bounds read vulnerability that allows attackers to trigger",
      "priority": "Routine",
      "severity": "Medium",
      "epss": 0.00353,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-72522",
      "url": "https://patchblox.com/security/cve/CVE-2026-72522",
      "title": "libexpat before 2.8.3 has an out-of-bounds read and resultant infinite loop because low surrogates are treated the same as high surrogates during Unicode processing in the *_toUtf16 functions.",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 6.2,
      "epss": 0.00193,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-56406",
      "url": "https://patchblox.com/security/cve/CVE-2026-56406",
      "title": "libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 6.9,
      "epss": 0.00188,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-56407",
      "url": "https://patchblox.com/security/cve/CVE-2026-56407",
      "title": "libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 6.9,
      "epss": 0.00188,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-56131",
      "url": "https://patchblox.com/security/cve/CVE-2026-56131",
      "title": "libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 4.9,
      "epss": 0.00183,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-56132",
      "url": "https://patchblox.com/security/cve/CVE-2026-56132",
      "title": "In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 6.9,
      "epss": 0.00159,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-56410",
      "url": "https://patchblox.com/security/cve/CVE-2026-56410",
      "title": "xmlwf in libexpat before 2.8.2 has an integer overflow in resolveSystemId.",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 6.9,
      "epss": 0.00145,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-56411",
      "url": "https://patchblox.com/security/cve/CVE-2026-56411",
      "title": "xmlwf in libexpat before 2.8.2 has an integer overflow in endDoctypeDecl via NOTATION declarations.",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 6.9,
      "epss": 0.00145,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2026-56409",
      "url": "https://patchblox.com/security/cve/CVE-2026-56409",
      "title": "xmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used.",
      "priority": "Routine",
      "severity": "Moderate",
      "cvss": 6.5,
      "epss": 0.00135,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    }
  ],
  "dataAsOf": "2026-11-12T19:57:06Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}