CVE-2026-93785 (GCVE-0-2026-93785)

Vulnerability from cvelistv5 – Published: 2026-09-24 16:02 – Updated: 2026-09-25 12:42
VLAI
Title
cifs: validate idmap key payload length
Summary
In the Linux kernel, the following vulnerability has been resolved: cifs: validate idmap key payload length The cifs.idmap key type stores its payload length in key->datalen, which is limited to U16_MAX. Accepting a larger key payload truncates the recorded length and can make later users interpret the payload using inconsistent bounds. Reject oversized preparsed payloads before allocating or copying them. This keeps key->datalen consistent with the stored data for both inline and separately allocated idmap payloads.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 21fed0d5b763b94a7d1568c27d0cce892ab8d43e , < 6cfeef221ac00d63c07f6122f58e6159bde69ca0 (git)
Affected: 21fed0d5b763b94a7d1568c27d0cce892ab8d43e , < 8b12f65d7caf16d124098cb4895a203367d35b57 (git)
Affected: 21fed0d5b763b94a7d1568c27d0cce892ab8d43e , < 455488cd5054bcc59db40fa1cc2c004031a5b2a5 (git)
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Linux Linux Affected: 3.2
Unaffected: 0 , < 3.2 (semver)
Unaffected: 6.12.111 , ≤ 6.12.* (semver)
Unaffected: 6.18.53 , ≤ 6.18.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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{
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          "programFiles": [
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: validate idmap key payload length\n\nThe cifs.idmap key type stores its payload length in key-\u003edatalen, which\nis limited to U16_MAX.  Accepting a larger key payload truncates the\nrecorded length and can make later users interpret the payload using\ninconsistent bounds.\n\nReject oversized preparsed payloads before allocating or copying them.\nThis keeps key-\u003edatalen consistent with the stored data for both inline\nand separately allocated idmap payloads."
        }
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      "providerMetadata": {
        "dateUpdated": "2026-09-25T12:42:50.782Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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      ],
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    "datePublished": "2026-09-24T16:02:18.964Z",
    "dateReserved": "2026-09-18T17:59:28.788Z",
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    "state": "PUBLISHED"
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                ],
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: validate idmap key payload length\n\nThe cifs.idmap key type stores its payload length in key-\u003edatalen, which\nis limited to U16_MAX.  Accepting a larger key payload truncates the\nrecorded length and can make later users interpret the payload using\ninconsistent bounds.\n\nReject oversized preparsed payloads before allocating or copying them.\nThis keeps key-\u003edatalen consistent with the stored data for both inline\nand separately allocated idmap payloads."
          }
        ],
        "id": "CVE-2026-93785",
        "lastModified": "2026-09-25T13:17:19.053",
        "metrics": {},
        "published": "2026-09-24T17:17:11.130",
        "references": [
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      "aggregate_severity": "not set",
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      "cve": "CVE-2026-93785",
      "id": "CVE-2026-93785",
      "initial_release_date": "2026-09-24T23:47:55Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-93785",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-93785.json",
      "version": "2"
    }
  }
}



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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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