CVE-2026-31694 (GCVE-0-2026-31694)

Vulnerability from cvelistv5 – Published: 2026-05-01 13:53 – Updated: 2026-07-02 13:44
VLAI?
Title
fuse: reject oversized dirents in page cache
Summary
In the Linux kernel, the following vulnerability has been resolved: fuse: reject oversized dirents in page cache fuse_add_dirent_to_cache() computes a serialized dirent size from the server-controlled namelen field and copies the dirent into a single page-cache page. The existing logic only checks whether the dirent fits in the remaining space of the current page and advances to a fresh page if not. It never checks whether the dirent itself exceeds PAGE_SIZE. As a result, a malicious FUSE server can return a dirent with namelen=4095, producing a serialized record size of 4120 bytes. On 4 KiB page systems this causes memcpy() to overflow the cache page by 24 bytes into the following kernel page. Reject dirents that cannot fit in a single page before copying them into the readdir cache.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 27992ef80770d61a57f6c3a551735b08cefdffa3 , < 7de93abfaae1b2dc94da8a07a36421bd073f1d8f (git)
Affected: 27992ef80770d61a57f6c3a551735b08cefdffa3 , < 474ce83c96a55f2eeb14dee2be375eeadfdacdf5 (git)
Affected: 27992ef80770d61a57f6c3a551735b08cefdffa3 , < 51a8de6c50bf947c8f534cd73da4c8f0a13e7bed (git)
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    Linux Linux Affected: 6.15
Unaffected: 0 , < 6.15 (semver)
Unaffected: 6.18.25 , ≤ 6.18.* (semver)
Unaffected: 7.0.2 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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{
  "containers": {
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        {
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          "product": "Linux",
          "programFiles": [
            "fs/fuse/readdir.c"
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              "operator": "OR"
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfuse: reject oversized dirents in page cache\n\nfuse_add_dirent_to_cache() computes a serialized dirent size from the\nserver-controlled namelen field and copies the dirent into a single\npage-cache page. The existing logic only checks whether the dirent fits\nin the remaining space of the current page and advances to a fresh page\nif not. It never checks whether the dirent itself exceeds PAGE_SIZE.\n\nAs a result, a malicious FUSE server can return a dirent with\nnamelen=4095, producing a serialized record size of 4120 bytes. On 4 KiB\npage systems this causes memcpy() to overflow the cache page by 24 bytes\ninto the following kernel page.\n\nReject dirents that cannot fit in a single page before copying them into\nthe readdir cache."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
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            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
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        "dateUpdated": "2026-07-02T13:44:23.365Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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        {
          "url": "https://git.kernel.org/stable/c/51a8de6c50bf947c8f534cd73da4c8f0a13e7bed"
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      ],
      "title": "fuse: reject oversized dirents in page cache",
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31694",
    "datePublished": "2026-05-01T13:53:36.048Z",
    "dateReserved": "2026-03-09T15:48:24.131Z",
    "dateUpdated": "2026-07-02T13:44:23.365Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


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