CVE-2026-80545
In the Linux kernel, the following vulnerability has been resolved:
s390/zcrypt: Improve EP11 CPRB length and overflow checks
The xcrb_msg_to_type6_ep11cprb_msgx() function lacks proper input validation, creating security vulnerabilities: 1. Missing minimum size validation: The ep11_cprb structure and subsequent payload fields (pld_tag, pld_lenfmt) are copied from userspace without verifying sufficient buffer length. 2. Arithmetic overflow in length calculations: CEIL4 alignment could overflow, bypassing size checks and enabling buffer overflows. 3. The payload is asn1 encoded but the function just uses a simple c struct overlay to access some fields of the payload.
Leer descripción completaMostrar menos
Fix by using size_t for length calculations, adding U32_MAX boundary checks after alignment, and validating minimum request size and minimum reply size before copying from userspace. Do a very simple asn1 parsing of the payload up to the function value field.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.18%
- Percentil entre todas las CVEs puntuadas: 7
- Fecha de la puntuación: 5/10/2026
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).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation90 % - Impacto principal
T1059Command and Scripting Interpreterexecution75 % - Impacto secundario
T1499.004Application or System Exploitationimpact65 % - Impacto secundario
T1565.001Stored Data Manipulationimpact70 %
AV:L/PR:L sin UI permite escalada local por desbordamiento de búfer (buffer overflow) en el kernel s390/zcrypt. Acceso local confirmado por vector CVSS. Impactos: ejecución de código del kernel, corrupción de memoria de datos, posible DoS.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-80545",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.8,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.8
}
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{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "e2c6d91eb8b1533753755f07803e47eceed263d0",
"lessThan": "2976b9d2e716c7e5487ca7c29a7bd076cf9adf08",
"versionType": "git"
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{
"status": "affected",
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"lessThan": "17ac0bc866fc624cd05f022dcd8b730c0af11bb1",
"versionType": "git"
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"programFiles": [
"drivers/s390/crypto/zcrypt_msgtype6.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "7.1"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "7.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "7.1.10",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/s390/crypto/zcrypt_msgtype6.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-26T15:17:08.870",
"references": [
{
"url": "https://git.kernel.org/stable/c/17ac0bc866fc624cd05f022dcd8b730c0af11bb1",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/2976b9d2e716c7e5487ca7c29a7bd076cf9adf08",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/zcrypt: Improve EP11 CPRB length and overflow checks\n\nThe xcrb_msg_to_type6_ep11cprb_msgx() function lacks proper input\nvalidation, creating security vulnerabilities:\n1. Missing minimum size validation: The ep11_cprb structure and\n subsequent payload fields (pld_tag, pld_lenfmt) are copied from\n userspace without verifying sufficient buffer length.\n2. Arithmetic overflow in length calculations: CEIL4 alignment could\n overflow, bypassing size checks and enabling buffer overflows.\n3. The payload is asn1 encoded but the function just uses a simple c\n struct overlay to access some fields of the payload.\n\nFix by using size_t for length calculations, adding U32_MAX boundary\nchecks after alignment, and validating minimum request size and\nminimum reply size before copying from userspace. Do a very simple\nasn1 parsing of the payload up to the function value field."
}
],
"lastModified": "2026-08-27T06:17:35.780",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}