CVE-2026-89489

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [[email protected]: fix comment style]

Severity

HIGH

CVSS score

7.8 (v3.1)

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-11 20:19:30.683000

Last modified

2026-10-19 09:17:42.653000

View original CVE JSON

{
  "id": "CVE-2026-89489",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:30.683",
  "lastModified": "2026-10-19T09:17:42.653",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nopenrisc: fix arbitrary kernel memory access via or1k_atomic syscall\n\nsys_or1k_atomic() (syscall 244 in the \"or1k\" ABI) takes two user\npointers, v1 and v2, and swaps the words they point to in hand-written\nassembly.\n\n    l.lwz   r29,0(r4)\n    l.lwz   r27,0(r5)\n    l.sw    0(r4),r27\n    l.sw    0(r5),r29\n\nThe pointers are not checked with access_ok(). The four memory\naccesses also have no exception table entries.\n\nA caller passes a kernel address as either pointer, and the syscall\nreads from and writes to it directly.\n\nThis gives an unprivileged process a kernel read/write primitive. It\noverwrites kernel data such as the sys_call_table, gaining code\nexecution in kernel context.\n\nCheck both pointers before entering the critical section. Add fixups\nfor the four memory accesses so faults on valid but unmapped user\naddresses return -EFAULT.\n\n[[email protected]: fix comment style]"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "arch/openrisc/kernel/entry.S"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "bf310718c6fa6adeee06d207a55489546d860e2c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "497cba0b02e5555d99fe9ee1dc478af743ab7f7a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "1f2e92e499d863f81df1732af59b4a3559969193",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "574ae2ac2b314aa33498cd2c28add106cbe644f2",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "a520e8cac54fb403f3800125b606f55fcad42cb9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "d64a75369cd0f2ee79afcc9d9ca34a3890989379",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "b53435c079c78f89f70a62dd5a322cca4e292b34",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a",
              "lessThan": "78004e9a87f240df03e2f73120d291763c32e0a7",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "arch/openrisc/kernel/entry.S"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "3.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.270",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.221",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.109",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.50",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "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
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1f2e92e499d863f81df1732af59b4a3559969193",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
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      "url": "https://git.kernel.org/stable/c/497cba0b02e5555d99fe9ee1dc478af743ab7f7a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/574ae2ac2b314aa33498cd2c28add106cbe644f2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/78004e9a87f240df03e2f73120d291763c32e0a7",
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    {
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    {
      "url": "https://git.kernel.org/stable/c/b53435c079c78f89f70a62dd5a322cca4e292b34",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/bf310718c6fa6adeee06d207a55489546d860e2c",
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    {
      "url": "https://git.kernel.org/stable/c/d64a75369cd0f2ee79afcc9d9ca34a3890989379",
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}