GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-74466 (GCVE-0-2026-74466)

Vulnerability from cvelistv5 – Published: 2026-08-15 12:27 – Updated: 2026-08-17 05:19
VLAI
Title
s390/zcrypt: Close speculative mem read possibility
Summary
In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Close speculative mem read possibility The domain value is extracted from a given CCA or EP11 ioctl struct when a CPRB is about to be sent. Thus this is a user controlled value. Under some special conditions (custom device node used, administrative load) this value is used as an array index after bounds checking, but without speculation barrier. Add the missing array_index_nospec() call to prevent speculative execution where this domain value is used.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: cfd68b33094e1a92249850ff3c3c92ae9112a541 , < 82b62eda68abfb7a33ac40f24b8c4128c2891148 (git)
Affected: cfd68b33094e1a92249850ff3c3c92ae9112a541 , < e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.18
Unaffected: 0 , < 5.18 (semver)
Unaffected: 7.1.8 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/s390/crypto/zcrypt_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "82b62eda68abfb7a33ac40f24b8c4128c2891148",
              "status": "affected",
              "version": "cfd68b33094e1a92249850ff3c3c92ae9112a541",
              "versionType": "git"
            },
            {
              "lessThan": "e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb",
              "status": "affected",
              "version": "cfd68b33094e1a92249850ff3c3c92ae9112a541",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/s390/crypto/zcrypt_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.18"
            },
            {
              "lessThan": "5.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.8",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/zcrypt: Close speculative mem read possibility\n\nThe domain value is extracted from a given CCA or EP11 ioctl struct\nwhen a CPRB is about to be sent. Thus this is a user controlled value.\nUnder some special conditions (custom device node used, administrative\nload) this value is used as an array index after bounds checking, but\nwithout speculation barrier.\n\nAdd the missing array_index_nospec() call to prevent speculative\nexecution where this domain value is used."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:19:56.359Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/82b62eda68abfb7a33ac40f24b8c4128c2891148"
        },
        {
          "url": "https://git.kernel.org/stable/c/e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb"
        }
      ],
      "title": "s390/zcrypt: Close speculative mem read possibility",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74466",
    "datePublished": "2026-08-15T12:27:05.020Z",
    "dateReserved": "2026-08-15T05:44:03.902Z",
    "dateUpdated": "2026-08-17T05:19:56.359Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74466",
      "date": "2026-09-04",
      "epss": "0.0017",
      "percentile": "0.06557"
    },
    "microsoft_vex": {
      "current_release_date": "2026-08-23T15:00:04.000Z",
      "cve": "CVE-2026-74466",
      "id": "msrc_CVE-2026-74466",
      "initial_release_date": "2026-08-23T15:00:04.000Z",
      "product_status:known_not_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "s390/zcrypt: Close speculative mem read possibility",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-74466.json",
      "version": "1"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74466\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T13:17:51.307\",\"lastModified\":\"2026-08-17T06:19:42.543\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\ns390/zcrypt: Close speculative mem read possibility\\n\\nThe domain value is extracted from a given CCA or EP11 ioctl struct\\nwhen a CPRB is about to be sent. Thus this is a user controlled value.\\nUnder some special conditions (custom device node used, administrative\\nload) this value is used as an array index after bounds checking, but\\nwithout speculation barrier.\\n\\nAdd the missing array_index_nospec() call to prevent speculative\\nexecution where this domain value is used.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/s390/crypto/zcrypt_api.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"cfd68b33094e1a92249850ff3c3c92ae9112a541\",\"lessThan\":\"82b62eda68abfb7a33ac40f24b8c4128c2891148\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"cfd68b33094e1a92249850ff3c3c92ae9112a541\",\"lessThan\":\"e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/s390/crypto/zcrypt_api.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.18\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.18\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.8\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/82b62eda68abfb7a33ac40f24b8c4128c2891148\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-21T11:33:04+00:00",
      "cve": "CVE-2026-74466",
      "id": "CVE-2026-74466",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: s390/zcrypt: Close speculative mem read possibility",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74466.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.