CVE-2026-23226 (GCVE-0-2026-23226)

Vulnerability from cvelistv5 – Published: 2026-02-18 14:53 – Updated: 2026-08-05 12:20
VLAI
Title
ksmbd: add chann_lock to protect ksmbd_chann_list xarray
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: add chann_lock to protect ksmbd_chann_list xarray ksmbd_chann_list xarray lacks synchronization, allowing use-after-free in multi-channel sessions (between lookup_chann_list() and ksmbd_chann_del). Adds rw_semaphore chann_lock to struct ksmbd_session and protects all xa_load/xa_store/xa_erase accesses.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1d9c4172110e645b383ff13eee759728d74f1a5d , < 4c2ca31608521895dd742a43beca4b4d29762345 (git)
Affected: 1d9c4172110e645b383ff13eee759728d74f1a5d , < e4a8a96a93d08570e0405cfd989a8a07e5b6ff33 (git)
Affected: 1d9c4172110e645b383ff13eee759728d74f1a5d , < 36ef605c0395b94b826a8c8d6f2697071173de6e (git)
Affected: 1d9c4172110e645b383ff13eee759728d74f1a5d , < 4f3a06cc57976cafa8c6f716646be6c79a99e485 (git)
Affected: b1caecbf34b8c8260d851ec4efde71f3694460b7 (git)
Affected: 91bbf9cb2387a0d76322e9a343bc6bc160f66b3f (git)
Affected: 853c416710b075153c1e1421e099ffbe5dac68ce (git)
Affected: 5.15.145 , < 5.16 (semver)
Affected: 6.1.29 , < 6.2 (semver)
Affected: 6.2.16 , < 6.3 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 6.3
Unaffected: 0 , < 6.3 (semver)
Unaffected: 6.12.77 , ≤ 6.12.* (semver)
Unaffected: 6.18.11 , ≤ 6.18.* (semver)
Unaffected: 6.19.1 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/mgmt/user_session.c",
            "fs/smb/server/mgmt/user_session.h",
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4c2ca31608521895dd742a43beca4b4d29762345",
              "status": "affected",
              "version": "1d9c4172110e645b383ff13eee759728d74f1a5d",
              "versionType": "git"
            },
            {
              "lessThan": "e4a8a96a93d08570e0405cfd989a8a07e5b6ff33",
              "status": "affected",
              "version": "1d9c4172110e645b383ff13eee759728d74f1a5d",
              "versionType": "git"
            },
            {
              "lessThan": "36ef605c0395b94b826a8c8d6f2697071173de6e",
              "status": "affected",
              "version": "1d9c4172110e645b383ff13eee759728d74f1a5d",
              "versionType": "git"
            },
            {
              "lessThan": "4f3a06cc57976cafa8c6f716646be6c79a99e485",
              "status": "affected",
              "version": "1d9c4172110e645b383ff13eee759728d74f1a5d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b1caecbf34b8c8260d851ec4efde71f3694460b7",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "91bbf9cb2387a0d76322e9a343bc6bc160f66b3f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "853c416710b075153c1e1421e099ffbe5dac68ce",
              "versionType": "git"
            },
            {
              "lessThan": "5.16",
              "status": "affected",
              "version": "5.15.145",
              "versionType": "semver"
            },
            {
              "lessThan": "6.2",
              "status": "affected",
              "version": "6.1.29",
              "versionType": "semver"
            },
            {
              "lessThan": "6.3",
              "status": "affected",
              "version": "6.2.16",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/mgmt/user_session.c",
            "fs/smb/server/mgmt/user_session.h",
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.3"
            },
            {
              "lessThan": "6.3",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.77",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.1",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.77",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.11",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.1",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.15.145",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.1.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.2.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: add chann_lock to protect ksmbd_chann_list xarray\n\nksmbd_chann_list xarray lacks synchronization, allowing use-after-free in\nmulti-channel sessions (between lookup_chann_list() and ksmbd_chann_del).\n\nAdds rw_semaphore chann_lock to struct ksmbd_session and protects\nall xa_load/xa_store/xa_erase accesses."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - ksmbd is the in-kernel SMB server listening on TCP port 445, directly reachable over the network.\nAC:L - The attacker controls both sides of the race by establishing multiple SMB connections (multi-channel session) and timing a disconnect on one while the other accesses the channel list. The attacker creates and controls the race condition.\nPR:L - The channel list is populated during ntlm_authenticate() or krb5_authenticate(), requiring valid SMB credentials to establish a session before the race can be triggered. This is post-authentication.\nUI:N - No user interaction is needed; the attacker initiates and controls all SMB connections and their timing.\nS:U - The vulnerability and its impact remain within the kernel security authority; no security boundary (e.g., VM, sandbox) is crossed.\nC:H - Use-after-free on struct channel allows reading freed memory that may be reallocated with attacker-controlled content, enabling arbitrary kernel memory disclosure including signing keys.\nI:H - Use-after-free enables heap spraying to replace the freed channel struct, allowing attacker-controlled data to be used as signing keys or function pointers, leading to arbitrary code execution.\nA:H - Use-after-free reliably causes kernel crashes (oops/panic) when the freed channel pointer is dereferenced, causing denial of service."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:20:44.508Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/4c2ca31608521895dd742a43beca4b4d29762345"
        },
        {
          "url": "https://git.kernel.org/stable/c/e4a8a96a93d08570e0405cfd989a8a07e5b6ff33"
        },
        {
          "url": "https://git.kernel.org/stable/c/36ef605c0395b94b826a8c8d6f2697071173de6e"
        },
        {
          "url": "https://git.kernel.org/stable/c/4f3a06cc57976cafa8c6f716646be6c79a99e485"
        }
      ],
      "title": "ksmbd: add chann_lock to protect ksmbd_chann_list xarray",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-23226",
    "datePublished": "2026-02-18T14:53:29.562Z",
    "dateReserved": "2026-01-13T15:37:45.987Z",
    "dateUpdated": "2026-08-05T12:20:44.508Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-23226",
      "date": "2026-08-22",
      "epss": "0.00423",
      "percentile": "0.35625"
    },
    "microsoft_vex": {
      "current_release_date": "2026-02-21T04:29:02.000Z",
      "cve": "CVE-2026-23226",
      "id": "msrc_CVE-2026-23226",
      "initial_release_date": "2026-02-02T00:00:00.000Z",
      "product_status:known_not_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "ksmbd: add chann_lock to protect ksmbd_chann_list xarray",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-23226.json",
      "version": "1"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-23226\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-02-18T16:22:32.363\",\"lastModified\":\"2026-06-17T10:21:08.290\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nksmbd: add chann_lock to protect ksmbd_chann_list xarray\\n\\nksmbd_chann_list xarray lacks synchronization, allowing use-after-free in\\nmulti-channel sessions (between lookup_chann_list() and ksmbd_chann_del).\\n\\nAdds rw_semaphore chann_lock to struct ksmbd_session and protects\\nall xa_load/xa_store/xa_erase accesses.\"},{\"lang\":\"es\",\"value\":\"Se ha resuelto la siguiente vulnerabilidad en el kernel de Linux:\\n\\nksmbd: a\u00f1adir chann_lock para proteger ksmbd_chann_list xarray\\n\\nksmbd_chann_list xarray carece de sincronizaci\u00f3n, permitiendo uso despu\u00e9s de liberaci\u00f3n en sesiones multicanal (entre lookup_chann_list() y ksmbd_chann_del).\\n\\nA\u00f1ade el sem\u00e1foro rw_semaphore chann_lock a la estructura ksmbd_session y protege todos los accesos xa_load/xa_store/xa_erase.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/smb/server/mgmt/user_session.c\",\"fs/smb/server/mgmt/user_session.h\",\"fs/smb/server/smb2pdu.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"1d9c4172110e645b383ff13eee759728d74f1a5d\",\"lessThan\":\"4c2ca31608521895dd742a43beca4b4d29762345\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1d9c4172110e645b383ff13eee759728d74f1a5d\",\"lessThan\":\"e4a8a96a93d08570e0405cfd989a8a07e5b6ff33\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1d9c4172110e645b383ff13eee759728d74f1a5d\",\"lessThan\":\"36ef605c0395b94b826a8c8d6f2697071173de6e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1d9c4172110e645b383ff13eee759728d74f1a5d\",\"lessThan\":\"4f3a06cc57976cafa8c6f716646be6c79a99e485\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"b1caecbf34b8c8260d851ec4efde71f3694460b7\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"91bbf9cb2387a0d76322e9a343bc6bc160f66b3f\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"853c416710b075153c1e1421e099ffbe5dac68ce\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5.15.145\",\"lessThan\":\"5.16\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.1.29\",\"lessThan\":\"6.2\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.2.16\",\"lessThan\":\"6.3\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/smb/server/mgmt/user_session.c\",\"fs/smb/server/mgmt/user_session.h\",\"fs/smb/server/smb2pdu.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.3\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.3\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.77\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.11\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.19.1\",\"lessThanOrEqual\":\"6.19.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.0\",\"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:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":8.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.8,\"impactScore\":5.9},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"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}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.3\",\"versionEndExcluding\":\"6.18.11\",\"matchCriteriaId\":\"AEB10F82-E8B1-4BB9-B91C-78490070AF53\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.19\",\"versionEndExcluding\":\"6.19.1\",\"matchCriteriaId\":\"EE543C0D-A06B-414F-A403-CB1E088F261E\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/36ef605c0395b94b826a8c8d6f2697071173de6e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/4c2ca31608521895dd742a43beca4b4d29762345\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4f3a06cc57976cafa8c6f716646be6c79a99e485\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/e4a8a96a93d08570e0405cfd989a8a07e5b6ff33\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-08-20T14:21:51+00:00",
      "cve": "CVE-2026-23226",
      "id": "CVE-2026-23226",
      "initial_release_date": "2026-02-18T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel (ksmbd): Arbitrary code execution due to use-after-free",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23226.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-06T01:26:39Z",
      "cve": "CVE-2026-23226",
      "id": "CVE-2026-23226",
      "initial_release_date": "2026-02-19T00:26:28Z",
      "product_status:known_not_affected": "332",
      "product_status:recommended": "4",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-23226",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-23226.json",
      "version": "10"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


Detection rules are retrieved from Rulezet.