{
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"dataVersion": "5.2",
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"assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
"state": "PUBLISHED",
"assignerShortName": "PSF",
"dateReserved": "2026-02-26T15:19:46.862Z",
"datePublished": "2026-06-03T14:29:39.727Z",
"dateUpdated": "2026-08-13T00:28:05.768Z"
},
"containers": {
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{
"defaultStatus": "unaffected",
"product": "CPython",
"repo": "https://github.com/python/cpython",
"vendor": "Python Software Foundation",
"versions": [
{
"version": "0",
"lessThan": "3.10.21",
"status": "affected",
"versionType": "python"
},
{
"version": "3.11.0",
"lessThan": "3.11.16",
"status": "affected",
"versionType": "python"
},
{
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"lessThan": "3.12.14",
"status": "affected",
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{
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{
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{
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}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "Seokchan Yoon (https://github.com/ch4n3-yoon)"
},
{
"lang": "en",
"type": "remediation reviewer",
"value": "Tim Peters (https://github.com/tim-one)"
},
{
"lang": "en",
"type": "remediation reviewer",
"value": "Bénédikt Tran (https://github.com/picnixz)"
},
{
"lang": "en",
"type": "remediation reviewer",
"value": "Serhiy Storchaka (https://github.com/serhiy-storchaka)"
},
{
"lang": "en",
"type": "remediation reviewer",
"value": "Stan Ulbrych (https://github.com/StanFromIreland)"
},
{
"lang": "en",
"type": "coordinator",
"value": "Seth Larson (https://github.com/sethmlarson)"
},
{
"lang": "en",
"type": "remediation reviewer",
"value": "Petr Viktorin (https://github.com/encukou)"
}
],
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"lang": "en",
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"base64": false,
"type": "text/html",
"value": "unicodedata.normalize() can take excessive CPU time when processing
specially crafted Unicode input containing long runs of combining characters
with alternating Canonical Combining Class values.
This affects all normalization forms."
}
],
"value": "unicodedata.normalize() can take excessive CPU time when processing\nspecially crafted Unicode input containing long runs of combining characters\nwith alternating Canonical Combining Class values.\nThis affects all normalization forms."
}
],
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"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
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"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 6.3,
"baseSeverity": "MEDIUM",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
"version": "4.0",
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"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
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"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-407",
"description": "CWE-407",
"lang": "en",
"type": "CWE"
}
]
}
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"shortName": "PSF",
"dateUpdated": "2026-08-13T00:28:05.768Z"
},
"references": [
{
"tags": [
"vendor-advisory"
],
"url": "https://mail.python.org/archives/list/security-announce@python.org/thread/PP5HB4K7727OBBM76KA2ILID76K3OZGZ/"
},
{
"tags": [
"patch"
],
"url": "https://github.com/python/cpython/pull/149080"
},
{
"tags": [
"issue-tracking"
],
"url": "https://github.com/python/cpython/issues/149079"
},
{
"tags": [
"patch"
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"url": "https://github.com/python/cpython/commit/6b505d1f41f8f3ea0fe5a4786d3a8fff1875cfc0"
},
{
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"url": "https://github.com/python/cpython/commit/991224b1e8311c85f198f6dd8208bf8cff7fc26f"
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{
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"patch"
],
"url": "https://github.com/python/cpython/commit/e322a1857084d521f79f45181b776f62e6acfc2c"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "Potential DoS via quadratic complexity in unicodedata.normalize()",
"x_generator": {
"engine": "Vulnogram 0.6.0"
}
},
"adp": [
{
"metrics": [
{
"other": {
"type": "ssvc",
"content": {
"timestamp": "2026-06-03T17:27:09.393265Z",
"id": "CVE-2026-3276",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
}
],
"title": "CISA ADP Vulnrichment",
"providerMetadata": {
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"dateUpdated": "2026-06-03T17:27:19.179Z"
}
},
{
"title": "CVE Program Container",
"references": [
{
"url": "http://www.openwall.com/lists/oss-security/2026/06/03/15"
}
],
"providerMetadata": {
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}
}
]
}
}