{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-43493",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-43493"
  ],
  "published": "2026-05-19T10:43:50Z",
  "summary": "crypto: pcrypt - Fix handling of MAY_BACKLOG requests",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: pcrypt - Fix handling of MAY_BACKLOG requests\n\nMAY_BACKLOG requests can return EBUSY.  Handle them by checking\nfor that value and filtering out EINPROGRESS notifications.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.175",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-43493"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ae7e95638d956d556d74b9abb9e780d3bd3dcd9e"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/1d7f07df450bac3301938fbc4251f2611be4084e"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/76641449b28979ebd6c02e9598367e119e385236"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9f1cbca178c03188e201ed175251372149bb25f2"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/eb34e243df57e32f4c08fa191f3602ea19076276"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/77d55bc8675ee851ed639dc9be77325a8024cf67"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/46271895ddfb1ba41f89f7e0dffbe9c2bcf7380a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/915b692e6cb723aac658c25eb82c58fd81235110"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-05T13:16:28Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 9.8,
      "cvss_v3_severity": "Critical",
      "scenario": "AV:N - pcrypt AEAD can sit under network-facing kernel crypto consumers such as kTLS/TIPC that process peer-supplied records or packets. In the highest reasonable deployment, a remote peer can drive the vulnerable encrypt/decrypt path through network traffic.\nAC:L - The trigger is child crypto backlog behavior under `CRYPTO_TFM_REQ_MAY_BACKLOG`; an attacker can induce queue pressure with concurrent requests or traffic. There is no race that depends on conditions outside the attacker's control.\nPR:N - The network-facing path requires no kernel privileges from the remote peer. The local AF_ALG AEAD path also has no capability gate, but the higher-severity network scenario is defensible.\nUI:N - No victim interaction is required once the affected crypto consumer is configured. The attacker only sends data or submits crypto requests.\nS:U - The bug corrupts kernel crypto/request state within the same kernel security authority. It is not a VM escape, IOMMU bypass, or other scope-changing boundary crossing.\nC:H - Mishandling `-EBUSY` can complete and free the request while the child request remains queued, leading to use-after-free on later callbacks. A kernel UAF is reasonably exploitable for high-impact information disclosure.\nI:H - The stale callback reuses freed request/padata memory and can drive list operations and completion paths on attacker-reclaimed objects. This is memory corruption with a plausible path to arbitrary write or control-flow corruption.\nA:H - At minimum, the premature completion and later queued callback can dereference or manipulate freed kernel memory. That can produce kernel oops/panic or list corruption, giving high availability impact."
    }
  }
}