CVE-2026-20243
Full vulnerability record from the local CVENow database.
Description
A vulnerability in the ALZ file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device. This vulnerability is due to improper boundary checks for content in ALZ files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains ALZ content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software.
Severity
HIGH
CVSS score
7.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-01 17:16:30.423000
Last modified
2026-10-25 17:10:00.197000
View original CVE JSON
{
"id": "CVE-2026-20243",
"sourceIdentifier": "[email protected]",
"published": "2026-07-01T17:16:30.423",
"lastModified": "2026-10-25T17:10:00.197",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability in the ALZ file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device.\r\n\r\nThis vulnerability is due to improper boundary checks for content in ALZ files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains ALZ content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software."
},
{
"lang": "es",
"value": "Una vulnerabilidad en el analizador de formato de archivo ALZ de ClamAV podría permitir a un atacante remoto no autenticado causar una condición de DoS, o posiblemente otros impactos expandidos, resultantes de corrupción de memoria en un dispositivo afectado.\n\nEsta vulnerabilidad se debe a comprobaciones de límites inadecuadas para el contenido en archivos ALZ durante el escaneo, lo que puede resultar en una escritura de búfer fuera de límites. Un atacante podría explotar esta vulnerabilidad al enviar un archivo manipulado que contiene contenido ALZ para ser escaneado por ClamAV en un dispositivo afectado. Un exploit exitoso podría permitir al atacante causar la terminación del proceso de escaneo de ClamAV, lo que resultaría en una condición de DoS en el software afectado."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Cisco",
"product": "Cisco Secure Endpoint",
"defaultStatus": "unknown",
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"source": "[email protected]",
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"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
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"integrityImpact": "NONE",
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"weaknesses": [
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"type": "Secondary",
"description": [
{
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"value": "CWE-120"
}
]
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