CVE-2026-3446
Estado: Pendiente de análisisMedia (6)—
When calling base64.b64decode() or related functions the decoding process would stop after encountering the first padded quad regardless of whether there was more information to be processed. This can lead to data being accepted which may be processed differently by other implementations. Use "validate=True" to enable stricter processing of base64 data.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/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
- Puntuación base: 6
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.22%
- Percentil entre todas las CVEs puntuadas: 12
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
CWE
- CWE-345
Referencias
- https://github.com/python/cpython/commit/1f9958f909c1b41a4ffc0b613ef8ec8fa5e7c474
- https://github.com/python/cpython/commit/4561f6418a691b3e89aef0901f53fe0dfb7f7c0e
- https://github.com/python/cpython/commit/e31c55121620189a0d1a07b689762d8ca9c1b7fa
- https://github.com/python/cpython/issues/145264
- https://github.com/python/cpython/pull/145267
- https://mail.python.org/archives/list/security-announce@python.org/thread/F5ZT5ICGJ6CKXVUJ34YBVY7WOZ5SHG53/
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-3446",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-3446",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-04-13T16:06:04.489473Z"
}
}
],
"cvssMetricV40": [
{
"type": "Secondary",
"source": "cna@python.org",
"cvssData": {
"Safety": "NOT_DEFINED",
"version": "4.0",
"Recovery": "NOT_DEFINED",
"baseScore": 6,
"Automatable": "NOT_DEFINED",
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/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",
"exploitMaturity": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"attackRequirements": "PRESENT",
"privilegesRequired": "LOW",
"subIntegrityImpact": "NONE",
"vulnIntegrityImpact": "HIGH",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "NONE",
"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"
}
}
]
},
"affected": [
{
"source": "cna@python.org",
"affectedData": [
{
"repo": "https://github.com/python/cpython",
"vendor": "Python Software Foundation",
"modules": [
"base64"
],
"product": "CPython",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "3.13.13",
"versionType": "python"
},
{
"status": "affected",
"version": "3.14.0",
"lessThan": "3.14.4",
"versionType": "python"
},
{
"status": "affected",
"version": "3.15.0a1",
"lessThan": "3.15.0a8",
"versionType": "python"
}
],
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-04-10T19:16:26.220",
"references": [
{
"url": "https://github.com/python/cpython/commit/1f9958f909c1b41a4ffc0b613ef8ec8fa5e7c474",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/commit/4561f6418a691b3e89aef0901f53fe0dfb7f7c0e",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/commit/e31c55121620189a0d1a07b689762d8ca9c1b7fa",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/issues/145264",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/pull/145267",
"source": "cna@python.org"
},
{
"url": "https://mail.python.org/archives/list/security-announce@python.org/thread/F5ZT5ICGJ6CKXVUJ34YBVY7WOZ5SHG53/",
"source": "cna@python.org"
}
],
"vulnStatus": "Awaiting Analysis",
"weaknesses": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"description": [
{
"lang": "en",
"value": "CWE-345"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "When calling base64.b64decode() or related functions the decoding process would stop after encountering the first padded quad regardless of whether there was more information to be processed. This can lead to data being accepted which may be processed differently by other implementations. Use \"validate=True\" to enable stricter processing of base64 data."
}
],
"lastModified": "2026-06-17T10:43:36.200",
"sourceIdentifier": "cna@python.org"
}