CVE-2026-6653
Full vulnerability record from the local CVENow database.
Description
Use After Free in libxml2's xmlParseInternalSubset from GNOME libxml2 version 2.9.11 to 2.11.0 allows a remote attacker to cause a denial-of-service via maliciously crafted XML input with improper entity resolution handling.
Severity
HIGH
CVSS score
7.0
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-06-22 14:17:51.113000
Last modified
2026-10-25 23:10:00.167000
View original CVE JSON
{
"id": "CVE-2026-6653",
"sourceIdentifier": "[email protected]",
"published": "2026-06-22T14:17:51.113",
"lastModified": "2026-10-25T23:10:00.167",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Use After Free in libxml2's xmlParseInternalSubset from GNOME libxml2 version 2.9.11 to 2.11.0 allows a remote attacker to cause a denial-of-service via maliciously crafted XML input with improper entity resolution handling."
},
{
"lang": "es",
"value": "Uso después de liberación en xmlParseInternalSubset de libxml2 desde la versión 2.9.11 hasta la 2.11.0 de GNOME libxml2 permite a un atacante remoto causar una denegación de servicio mediante una entrada XML maliciosamente elaborada con un manejo inadecuado de la resolución de entidades."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "GNOME",
"product": "libxml2",
"defaultStatus": "unaffected",
"packageName": "libxml2",
"repo": "https://gitlab.gnome.org/GNOME/libxml2",
"versions": [
{
"version": "2.9.11",
"lessThan": "2.11.0",
"versionType": "semver",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"baseScore": 7.0,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"attackRequirements": "NONE",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "LOW",
"vulnAvailabilityImpact": "LOW",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"subAvailabilityImpact": "NONE",
"exploitMaturity": "PROOF_OF_CONCEPT",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 3.9,
"impactScore": 5.9
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-06-22T15:51:00.508541Z",
"id": "CVE-2026-6653",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-416"
},
{
"lang": "en",
"value": "CWE-611"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:a:xmlsoft:libxml2:*:*:*:*:*:*:*:*",
"versionStartIncluding": "2.9.11",
"versionEndIncluding": "2.11.0",
"matchCriteriaId": "52D9DF90-B6D6-4520-AB52-DCC1F17711F4"
}
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}
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}
],
"references": [
{
"url": "https://bugs.launchpad.net/ubuntu/+source/libxml2/+bug/2141260",
"source": "[email protected]",
"tags": [
"Exploit",
"Issue Tracking",
"Third Party Advisory"
]
},
{
"url": "https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1058",
"source": "[email protected]",
"tags": [
"Exploit",
"Issue Tracking",
"Patch"
]
}
]
}