CVE-2026-76151
Out-of-bounds read (buffer over-read) in the HTTP Cache-Control response header parsing in the QtNetwork module in Qt Group Qt 6.0.0 through 6.8.8, and 6.9.0 through 6.11.1, allows remote attackers to cause a denial of service (application crash) via an excessively large Cache-Control header value returned by an untrusted or compromised HTTP server to an application using QNetworkAccessManager. Only the client side of the connection is affected and 32-bit builds are not affected; the out-of-bounds access is read-only, with no information disclosure and no code execution.
CVSS
- Version: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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:N/R:A/V:X/RE:X/U:X
- Base score: 4.6
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.67%
- Percentile among all scored CVEs: 50
- Score date: 10/4/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-125, CWE-197
References
Raw JSON (NVD)
Show
{
"id": "CVE-2026-76151",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-76151",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-09-16T13:19:18.218493Z"
}
}
],
"cvssMetricV40": [
{
"type": "Secondary",
"source": "a59d8014-47c4-4630-ab43-e1b13cbe58e3",
"cvssData": {
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"version": "4.0",
"Recovery": "AUTOMATIC",
"baseScore": 4.6,
"Automatable": "NO",
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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:N/R:A/V:X/RE:X/U:X",
"exploitMaturity": "UNREPORTED",
"providerUrgency": "NOT_DEFINED",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"privilegesRequired": "NONE",
"subIntegrityImpact": "NONE",
"vulnIntegrityImpact": "NONE",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "HIGH",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"confidentialityRequirement": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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"affected": [
{
"source": "a59d8014-47c4-4630-ab43-e1b13cbe58e3",
"affectedData": [
{
"repo": "https://code.qt.io/cgit/qt/qtbase.git",
"vendor": "qt",
"modules": [
"qtbase"
],
"product": "qt",
"versions": [
{
"status": "affected",
"version": "6.0.0",
"lessThan": "6.8.9",
"versionType": "python"
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{
"status": "affected",
"version": "6.9.0",
"lessThan": "6.11.2",
"versionType": "python"
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"defaultStatus": "unaffected"
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}
],
"published": "2026-09-16T10:16:52.660",
"references": [
{
"url": "https://codereview.qt-project.org/c/qt/qtbase/+/752129",
"source": "a59d8014-47c4-4630-ab43-e1b13cbe58e3"
}
],
"vulnStatus": "Awaiting Analysis",
"weaknesses": [
{
"type": "Secondary",
"source": "a59d8014-47c4-4630-ab43-e1b13cbe58e3",
"description": [
{
"lang": "en",
"value": "CWE-125"
},
{
"lang": "en",
"value": "CWE-197"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Out-of-bounds read (buffer over-read) in the HTTP Cache-Control response header parsing in the QtNetwork module in Qt Group Qt 6.0.0 through 6.8.8, and 6.9.0 through 6.11.1, allows remote attackers to cause a denial of service (application crash) via an excessively large Cache-Control header value returned by an untrusted or compromised HTTP server to an application using QNetworkAccessManager. Only the client side of the connection is affected and 32-bit builds are not affected; the out-of-bounds access is read-only, with no information disclosure and no code execution."
}
],
"lastModified": "2026-09-18T19:21:34.307",
"sourceIdentifier": "a59d8014-47c4-4630-ab43-e1b13cbe58e3"
}