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CVE-2026-80544

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Improve EP11 CPRB domain handling with ASN.1 parsing The zcrypt_msgtype6_send_ep11_cprb() function uses fragile struct overlays to access and modify the domain field in the EP11 CPRB payload, creating maintainability and security concerns: 1. Struct overlay approach (pld_hdr) assumes fixed payload structure and doesn't validate the actual ASN.1 encoding. 2. Complex length format detection logic is error-prone and doesn't properly validate bounds at each parsing step. 3. Direct struct member access bypasses proper ASN.1 validation. Fix by replacing struct overlays with explicit ASN.1 parsing that validates each field (payload tag/length, function tag/length/value, optional domain tag/length/value) with proper bounds checking at every step. Add asn1_int_encode() helper function to safely write integer values with correct endianness conversion. This makes the code consistent with the validation pattern introduced with the rework of the xcrb_msg_to_type6_ep11cprb_msgx() function.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-26 15:17:08.763000
Last modified
2026-10-21 13:19:54.203000
View original CVE JSON
{
  "id": "CVE-2026-80544",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-26T15:17:08.763",
  "lastModified": "2026-10-21T13:19:54.203",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/zcrypt: Improve EP11 CPRB domain handling with ASN.1 parsing\n\nThe zcrypt_msgtype6_send_ep11_cprb() function uses fragile struct\noverlays to access and modify the domain field in the EP11 CPRB\npayload, creating maintainability and security concerns:\n1. Struct overlay approach (pld_hdr) assumes fixed payload structure\n   and doesn't validate the actual ASN.1 encoding.\n2. Complex length format detection logic is error-prone and doesn't\n   properly validate bounds at each parsing step.\n3. Direct struct member access bypasses proper ASN.1 validation.\n\nFix by replacing struct overlays with explicit ASN.1 parsing that\nvalidates each field (payload tag/length, function tag/length/value,\noptional domain tag/length/value) with proper bounds checking at every\nstep. Add asn1_int_encode() helper function to safely write integer\nvalues with correct endianness conversion. This makes the code\nconsistent with the validation pattern introduced with the rework of\nthe xcrb_msg_to_type6_ep11cprb_msgx() function."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/s390/crypto/zcrypt_msgtype6.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "20b0b0159390fa5c00a435195649680fefda81e0",
              "lessThan": "00a44ff06bcffb68b9cd7e90d2259b7d14b82b18",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e2c6d91eb8b1533753755f07803e47eceed263d0",
              "lessThan": "db21b2cf6dd0af5ffd08931e0a9fcda5a0473220",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e2c6d91eb8b1533753755f07803e47eceed263d0",
              "lessThan": "0864a163783bff109b548266921829ea794edc93",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f9da85d4780515f65983e0af151458599adaef3d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6.12.114",
              "lessThan": "6.13",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/s390/crypto/zcrypt_msgtype6.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.10",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T19:16:53.738849Z",
          "id": "CVE-2026-80544",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/00a44ff06bcffb68b9cd7e90d2259b7d14b82b18",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/0864a163783bff109b548266921829ea794edc93",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/db21b2cf6dd0af5ffd08931e0a9fcda5a0473220",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
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}