CVE-2026-45186

In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.

CVSS v3 2.9 LOW

2.9^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.4 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/libexpat/libexpat/pull/1216	Exploit Issue Tracking Patch
http://www.openwall.com/lists/oss-security/2026/05/11/16	Mailing List Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:22715
https://access.redhat.com/errata/RHSA-2026:22721
https://access.redhat.com/errata/RHSA-2026:23230
https://access.redhat.com/errata/RHSA-2026:26319
https://access.redhat.com/errata/RHSA-2026:27201
https://access.redhat.com/errata/RHSA-2026:29197
https://access.redhat.com/errata/RHSA-2026:58981
https://access.redhat.com/security/cve/CVE-2026-45186
https://bugzilla.redhat.com/show_bug.cgi?id=2468575
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-45186.json

Configurations

Configuration 1 (hide)

cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-10 07:16

Updated : 2026-09-16 13:17

NVD link : CVE-2026-45186

Mitre link : CVE-2026-45186

CVE.ORG link : CVE-2026-45186

JSON object : View

Products Affected

libexpat_project

libexpat

CWE

CWE-407

Inefficient Algorithmic Complexity

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"versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [{"status": "affected", "version": "V3.1.5", "lessThan": "V3.1.6", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP", "versions": [{"status": "affected", "version": "V3.1.5", "lessThan": "V3.1.6", "versionType": "custom"}], "defaultStatus": "unknown"}]}], "published": "2026-05-10T07:16:07.883", "references": [{"url": "https://github.com/libexpat/libexpat/pull/1216", "tags": ["Exploit", "Issue Tracking", "Patch"], "source": "cve@mitre.org"}, {"url": "http://www.openwall.com/lists/oss-security/2026/05/11/16", "tags": ["Mailing List", "Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://access.redhat.com/errata/RHSA-2026:22715", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": 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"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-45186.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "cve@mitre.org", "description": [{"lang": "en", "value": "CWE-407"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-407"}]}], "descriptions": [{"lang": "en", "value": "In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input."}, {"lang": "es", "value": "En libexpat antes de 2.8.1, la complejidad computacional de las comprobaciones de colisi\u00f3n de nombres de atributos permite una denegaci\u00f3n de servicio a trav\u00e9s de una entrada XML manipulada de tama\u00f1o moderado."}], "lastModified": "2026-09-16T13:17:58.967", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1567664C-530C-4589-B1C7-9982976B90F4", "versionEndExcluding": "2.8.1"}], "operator": "OR"}]}], "sourceIdentifier": "cve@mitre.org"}