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CVE-2026-98119

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: netfs: break unbuffered write when netfs_alloc_subrequest() fails syzbot reported a null-ptr-deref below [1] following a fault injection in netfs_alloc_subrequest(). [0] When netfs_alloc_subrequest() fails, subreq is NULL. Later, netfs_prepare_write() tries to initialize members of subreq(e.g., source), the issue in [1] is triggered. Let's handle the error of netfs_prepare_write() properly. [0] FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 Call Trace: netfs_alloc_subrequest+0x116/0x3f0 netfs_prepare_write+0x76/0x7b0 netfs_unbuffered_write+0x75c/0x2020 netfs_unbuffered_write_iter_locked+0x7d6/0xa80 netfs_unbuffered_write_iter+0x442/0x720 v9fs_file_write_iter+0xbf/0x100 vfs_write+0x6ac/0x1050 [1] KASAN: null-ptr-deref in range [0x00000000000000a8-0x00000000000000af] RIP: 0010:netfs_prepare_write+0xbc/0x7b0 fs/netfs/write_issue.c:173 Call Trace: netfs_unbuffered_write+0x75c/0x2020 fs/netfs/direct_write.c:111 netfs_unbuffered_write_iter_locked+0x7d6/0xa80 fs/netfs/direct_write.c:290 netfs_unbuffered_write_iter+0x442/0x720 fs/netfs/direct_write.c:382 v9fs_file_write_iter+0xbf/0x100 fs/9p/vfs_file.c:409 new_sync_write fs/read_write.c:595 [inline]

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-25 11:17:43.140000
Last modified
2026-10-26 18:36:45.120000
View original CVE JSON
{
  "id": "CVE-2026-98119",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-25T11:17:43.140",
  "lastModified": "2026-10-26T18:36:45.120",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: break unbuffered write when netfs_alloc_subrequest() fails\n\nsyzbot reported a null-ptr-deref below [1] following a fault injection in\nnetfs_alloc_subrequest(). [0]\n\nWhen netfs_alloc_subrequest() fails, subreq is NULL.\nLater, netfs_prepare_write() tries to initialize members of\nsubreq(e.g., source), the issue in [1] is triggered.\n\nLet's handle the error of netfs_prepare_write() properly.\n\n[0]\nFAULT_INJECTION: forcing a failure.\nname failslab, interval 1, probability 0, space 0, times 0\nCall Trace:\n netfs_alloc_subrequest+0x116/0x3f0\n netfs_prepare_write+0x76/0x7b0\n netfs_unbuffered_write+0x75c/0x2020\n netfs_unbuffered_write_iter_locked+0x7d6/0xa80\n netfs_unbuffered_write_iter+0x442/0x720\n v9fs_file_write_iter+0xbf/0x100\n vfs_write+0x6ac/0x1050\n\n[1]\nKASAN: null-ptr-deref in range [0x00000000000000a8-0x00000000000000af]\nRIP: 0010:netfs_prepare_write+0xbc/0x7b0 fs/netfs/write_issue.c:173\nCall Trace:\n netfs_unbuffered_write+0x75c/0x2020 fs/netfs/direct_write.c:111\n netfs_unbuffered_write_iter_locked+0x7d6/0xa80 fs/netfs/direct_write.c:290\n netfs_unbuffered_write_iter+0x442/0x720 fs/netfs/direct_write.c:382\n v9fs_file_write_iter+0xbf/0x100 fs/9p/vfs_file.c:409\n new_sync_write fs/read_write.c:595 [inline]"
    }
  ],
  "affected": [
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      "affectedData": [
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          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
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          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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          "product": "Linux",
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          "programFiles": [
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            "fs/netfs/write_issue.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
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              "version": "6.10",
              "status": "affected"
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              "version": "0",
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              "versionType": "semver",
              "status": "unaffected"
            },
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              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.7",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
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          "negate": false,
          "cpeMatch": [
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  "references": [
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      "url": "https://git.kernel.org/stable/c/19f246c795e940dc5f11cd5bc0cb1e81bc7b7090",
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}