OESA-2026-2975 (CVE-2026-56403)

Vulnerability from osv_openeuler – Published: 2026-07-09 11:11 – Updated: 2026-08-06 11:11 – Source website
VLAI
Summary
expat security update
Details

expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.

Security Fix(es):

libexpat before 2.8.2 has an integer overflow in storeAtts.(CVE-2026-56403)

libexpat before 2.8.2 has an integer overflow in addBinding.(CVE-2026-56404)

libexpat before 2.8.2 has an integer overflow in getAttributeId.(CVE-2026-56405)

libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.(CVE-2026-56406)

libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.(CVE-2026-56407)

libexpat before 2.8.2 has an integer overflow in copyString.(CVE-2026-56408)

xmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used.(CVE-2026-56409)

xmlwf in libexpat before 2.8.2 has an integer overflow in resolveSystemId.(CVE-2026-56410)

xmlwf in libexpat before 2.8.2 has an integer overflow in endDoctypeDecl via NOTATION declarations.(CVE-2026-56411)

libexpat before 2.8.2 does not consider XML_TOK_DATA_CHARS in doCdataSection and thus lacks handler call depth tracking for various calls from within handlers in cases of a policy violation. Thus, a use-after-free can occur. NOTE: this issue exists because of an incomplete fix for CVE-2026-50219.(CVE-2026-56412)

Severity
6.9 (Medium)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "expat-2.5.0-23.oe2403sp1.aarch64.rpm",
          "expat-debuginfo-2.5.0-23.oe2403sp1.aarch64.rpm",
          "expat-debugsource-2.5.0-23.oe2403sp1.aarch64.rpm",
          "expat-devel-2.5.0-23.oe2403sp1.aarch64.rpm"
        ],
        "noarch": [
          "expat-help-2.5.0-23.oe2403sp1.noarch.rpm"
        ],
        "src": [
          "expat-2.5.0-23.oe2403sp1.src.rpm"
        ],
        "x86_64": [
          "expat-2.5.0-23.oe2403sp1.x86_64.rpm",
          "expat-debuginfo-2.5.0-23.oe2403sp1.x86_64.rpm",
          "expat-debugsource-2.5.0-23.oe2403sp1.x86_64.rpm",
          "expat-devel-2.5.0-23.oe2403sp1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP1",
        "name": "expat",
        "purl": "pkg:rpm/openEuler/expat\u0026distro=openEuler-24.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.5.0-23.oe2403sp1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Medium"
  },
  "details": "expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.\r\n\r\nSecurity Fix(es):\n\nlibexpat before 2.8.2 has an integer overflow in storeAtts.(CVE-2026-56403)\n\nlibexpat before 2.8.2 has an integer overflow in addBinding.(CVE-2026-56404)\n\nlibexpat before 2.8.2 has an integer overflow in getAttributeId.(CVE-2026-56405)\n\nlibexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.(CVE-2026-56406)\n\nlibexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.(CVE-2026-56407)\n\nlibexpat before 2.8.2 has an integer overflow in copyString.(CVE-2026-56408)\n\nxmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used.(CVE-2026-56409)\n\nxmlwf in libexpat before 2.8.2 has an integer overflow in resolveSystemId.(CVE-2026-56410)\n\nxmlwf in libexpat before 2.8.2 has an integer overflow in endDoctypeDecl via NOTATION declarations.(CVE-2026-56411)\n\nlibexpat before 2.8.2 does not consider XML_TOK_DATA_CHARS in doCdataSection and thus lacks handler call depth tracking for various calls from within handlers in cases of a policy violation. Thus, a use-after-free can occur. NOTE: this issue exists because of an incomplete fix for CVE-2026-50219.(CVE-2026-56412)",
  "id": "OESA-2026-2975",
  "modified": "2026-08-06T11:11:52Z",
  "published": "2026-07-09T11:11:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2975"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56403"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56404"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56405"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56406"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56407"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56408"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56409"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56410"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56411"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56412"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "expat security update",
  "upstream": [
    "CVE-2026-56403",
    "CVE-2026-56404",
    "CVE-2026-56405",
    "CVE-2026-56406",
    "CVE-2026-56407",
    "CVE-2026-56408",
    "CVE-2026-56409",
    "CVE-2026-56410",
    "CVE-2026-56411",
    "CVE-2026-56412"
  ]
}



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