CVE-2021-38690
Status: ModifiedCritical (9.8)—
A stack buffer overflow vulnerability has been reported to affect QNAP device running QVR Elite, QVR Pro, QVR Guard. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of QVR Elite, QVR Pro, QVR Guard: QuTS hero h5.0.0: QVR Elite 2.1.4.0 (2021/12/06) and later QuTS hero h4.5.4: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 5.0.0: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 4.5.4: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 4.5.4: QVR Pro 2.1.3.0 (2021/12/06) and later QTS 5.0.0: QVR Pro 2.1.3.0 (2021/12/06) and later QTS 4.5.4: QVR Guard 2.1.3.0 (2021/12/06) and later QTS 5.0.0: QVR Guard 2.1.3.0 (2021/12/06) and later
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Base score: 9.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.30%
- Percentile among all scored CVEs: 69
- Score date: 10/5/2026
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 (3)
CWEs
- CWE-120
- CWE-787
References
Raw JSON (NVD)
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{
"id": "CVE-2021-38690",
"cveTags": [],
"metrics": {
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{
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"published": "2022-01-14T01:15:08.613",
"references": [
{
"url": "https://www.qnap.com/en/security-advisory/qsa-21-59",
"tags": [
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"source": "security@qnapsecurity.com.tw"
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{
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"weaknesses": [
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"source": "security@qnapsecurity.com.tw",
"description": [
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"value": "CWE-120"
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"description": [
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"descriptions": [
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"lang": "en",
"value": "A stack buffer overflow vulnerability has been reported to affect QNAP device running QVR Elite, QVR Pro, QVR Guard. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of QVR Elite, QVR Pro, QVR Guard: QuTS hero h5.0.0: QVR Elite 2.1.4.0 (2021/12/06) and later QuTS hero h4.5.4: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 5.0.0: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 4.5.4: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 4.5.4: QVR Pro 2.1.3.0 (2021/12/06) and later QTS 5.0.0: QVR Pro 2.1.3.0 (2021/12/06) and later QTS 4.5.4: QVR Guard 2.1.3.0 (2021/12/06) and later QTS 5.0.0: QVR Guard 2.1.3.0 (2021/12/06) and later"
},
{
"lang": "es",
"value": "Se ha informado de una vulnerabilidad de desbordamiento del búfer de la pila que afecta al dispositivo de QNAP que ejecuta QVR Elite, QVR Pro, QVR Guard. Si es explotado, esta vulnerabilidad permite a atacantes ejecutar código arbitrario. Ya hemos corregido esta vulnerabilidad en las siguientes versiones de QVR Elite, QVR Pro, QVR Guard: QuTS hero h5.0.0: QVR Elite 2.1.4.0 (06/12/2021) y posteriores QuTS hero h4.5.4: QVR Elite 2.1.4.0 (06/12/2021) y posteriores QTS 5.0.0: QVR Elite 2.1.4.0 (06/12/2021) y posteriores QTS 4.5.4: QVR Elite 2.1.4.0 (06/12/2021) y posteriores QTS 4.5.4: QVR Pro 2.1.3.0 (06/12/2021) y posteriores QTS 5.0.0: QVR Pro 2.1.3.0 (06/12/2021) y posteriores QTS 4.5.4: QVR Guard 2.1.3.0 (06/12/2021) y posteriores QTS 5.0.0: QVR Guard 2.1.3.0 (06/12/2021) y posteriores"
}
],
"lastModified": "2026-06-17T04:02:35.817",
"configurations": [
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"sourceIdentifier": "security@qnapsecurity.com.tw"
}