Vulnerability-Lookup

GHSA-9VR4-4R2H-JQV2

Vulnerability from github – Published: 2026-09-25 12:31 – Updated: 2026-10-26 21:35

Details

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

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-98119"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-25T11:17:43Z",
    "severity": "MODERATE"
  },
  "details": "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\u0027s 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]",
  "id": "GHSA-9vr4-4r2h-jqv2",
  "modified": "2026-10-26T21:35:45Z",
  "published": "2026-09-25T12:31:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98119"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/19f246c795e940dc5f11cd5bc0cb1e81bc7b7090"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8fb45a934661419c04a44d4cfea1e0df7dcf2805"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cf6f93b8b06acf57de62dacbe71a3b99c68656a7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-98119 (GCVE-0-2026-98119)

Vulnerability from cvelistv5 – Published: 2026-09-25 10:36 – Updated: 2026-10-19 09:14

Title

netfs: break unbuffered write when netfs_alloc_subrequest() fails

Summary

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

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6641 records in the last 180 days details

References

3 references

URL	Tags
https://git.kernel.org/stable/c/cf6f93b8b06acf57d…
https://git.kernel.org/stable/c/19f246c795e940dc5…
https://git.kernel.org/stable/c/8fb45a934661419c0…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 288ace2f57c9d06dd2e42bd80d03747d879a4068 , < cf6f93b8b06acf57de62dacbe71a3b99c68656a7 (git) Affected: 288ace2f57c9d06dd2e42bd80d03747d879a4068 , < 19f246c795e940dc5f11cd5bc0cb1e81bc7b7090 (git) Affected: 288ace2f57c9d06dd2e42bd80d03747d879a4068 , < 8fb45a934661419c04a44d4cfea1e0df7dcf2805 (git)
Linux	Linux	Affected: 6.10 Unaffected: 0 , < 6.10 (semver) Unaffected: 6.18.53 , ≤ 6.18.* (semver) Unaffected: 7.2.7 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/netfs/direct_write.c",
            "fs/netfs/write_issue.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "cf6f93b8b06acf57de62dacbe71a3b99c68656a7",
              "status": "affected",
              "version": "288ace2f57c9d06dd2e42bd80d03747d879a4068",
              "versionType": "git"
            },
            {
              "lessThan": "19f246c795e940dc5f11cd5bc0cb1e81bc7b7090",
              "status": "affected",
              "version": "288ace2f57c9d06dd2e42bd80d03747d879a4068",
              "versionType": "git"
            },
            {
              "lessThan": "8fb45a934661419c04a44d4cfea1e0df7dcf2805",
              "status": "affected",
              "version": "288ace2f57c9d06dd2e42bd80d03747d879a4068",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/netfs/direct_write.c",
            "fs/netfs/write_issue.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.53",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.53",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.7",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "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\u0027s 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]"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T09:14:11.462Z",
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        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/19f246c795e940dc5f11cd5bc0cb1e81bc7b7090"
        },
        {
          "url": "https://git.kernel.org/stable/c/8fb45a934661419c04a44d4cfea1e0df7dcf2805"
        }
      ],
      "title": "netfs: break unbuffered write when netfs_alloc_subrequest() fails",
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        "engine": "bippy-1.2.0"
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98119",
    "datePublished": "2026-09-25T10:36:03.524Z",
    "dateReserved": "2026-09-25T10:25:14.317Z",
    "dateUpdated": "2026-10-19T09:14:11.462Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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