GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2025-38737 (GCVE-0-2025-38737)

Vulnerability from cvelistv5 – Published: 2025-09-05 17:20 – Updated: 2026-08-05 12:04
VLAI
Title
cifs: Fix oops due to uninitialised variable
Summary
In the Linux kernel, the following vulnerability has been resolved: cifs: Fix oops due to uninitialised variable Fix smb3_init_transform_rq() to initialise buffer to NULL before calling netfs_alloc_folioq_buffer() as netfs assumes it can append to the buffer it is given. Setting it to NULL means it should start a fresh buffer, but the value is currently undefined.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: a2906d3316fc19bf0ade84618bb73eab604c447e , < 4931fe2dbe1cc0e7d350a4b51b0b330e43971d98 (git)
Affected: a2906d3316fc19bf0ade84618bb73eab604c447e , < 6adaa9fae36f848afa7278945d725e197e33c496 (git)
Affected: a2906d3316fc19bf0ade84618bb73eab604c447e , < 453a6d2a68e54a483d67233c6e1e24c4095ee4be (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.44 , ≤ 6.12.* (semver)
Unaffected: 6.16.4 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (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/client/smb2ops.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4931fe2dbe1cc0e7d350a4b51b0b330e43971d98",
              "status": "affected",
              "version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
              "versionType": "git"
            },
            {
              "lessThan": "6adaa9fae36f848afa7278945d725e197e33c496",
              "status": "affected",
              "version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
              "versionType": "git"
            },
            {
              "lessThan": "453a6d2a68e54a483d67233c6e1e24c4095ee4be",
              "status": "affected",
              "version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2ops.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.12"
            },
            {
              "lessThan": "6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.44",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.16.*",
              "status": "unaffected",
              "version": "6.16.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.17",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.44",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.16.4",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: Fix oops due to uninitialised variable\n\nFix smb3_init_transform_rq() to initialise buffer to NULL before calling\nnetfs_alloc_folioq_buffer() as netfs assumes it can append to the buffer it\nis given.  Setting it to NULL means it should start a fresh buffer, but the\nvalue is currently undefined."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The vulnerable path is the SMB3 client transport-encryption routine, and whether it is entered is dictated by server-supplied SESSION_SETUP/TREE_CONNECT flags (SMB2_SESSION_FLAG_ENCRYPT_DATA / SHI1005_FLAGS_ENCRYPT_DATA), so a remote or MITM SMB server across the network selects the vulnerable path and receives the leaked plaintext of the corrupted buffer.\nAC:L - Once encryption is negotiated, every write with a payload runs the uninitialised pointer through netfs_alloc_folioq_buffer(); the stack slot is reachable and groomable via ordinary syscall sequences on the writing task\u0027s kernel stack, with no condition outside the attacker\u0027s influence.\nPR:N - The remote SMB server presents no credentials to the client and needs none to set the encryption flags that gate the path; on the local side, any user holding a normal write handle to the mounted share triggers it with no elevated privileges.\nUI:N - An already-mounted share reaches the path through routine writeback and automatic reconnect (which re-runs session setup and tree connect), so no victim action beyond normal use of an existing mount is required.\nS:U - The wild reads, writes and bogus folio_put()s all occur within the kernel\u0027s own memory and the same security authority; no VM, IOMMU or sandbox boundary is crossed.\nC:H - Because *_buffer is never reassigned, the garbage folio_queue is used as the ITER_SOURCE for crypt_message(), so arbitrary kernel memory pointed to by the stale chain is encrypted and sent to the remote peer, and freeing the chain yields further use-after-free read primitives.\nI:H - netfs_alloc_folioq_buffer() writes through the garbage pointer (tail-\u003enext = p, p-\u003eprev = tail, folioq_append_mark()), and cifs_copy_iter_to_folioq() then copies attacker-supplied write() data into folios derived from that chain, giving a content-controlled kernel write suitable for control-flow hijacking.\nA:H - The commit is titled \"Fix oops due to uninitialised variable\" \u2014 dereferencing the indeterminate pointer oopses the kernel, and the resulting folio_queue/folio refcount corruption and bogus frees cause further panics."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:04:26.998Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/4931fe2dbe1cc0e7d350a4b51b0b330e43971d98"
        },
        {
          "url": "https://git.kernel.org/stable/c/6adaa9fae36f848afa7278945d725e197e33c496"
        },
        {
          "url": "https://git.kernel.org/stable/c/453a6d2a68e54a483d67233c6e1e24c4095ee4be"
        }
      ],
      "title": "cifs: Fix oops due to uninitialised variable",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-38737",
    "datePublished": "2025-09-05T17:20:37.719Z",
    "dateReserved": "2025-04-16T04:51:24.034Z",
    "dateUpdated": "2026-08-05T12:04:26.998Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-38737",
      "date": "2026-09-18",
      "epss": "0.00371",
      "percentile": "0.30928"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "fs/smb/client/smb2ops.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "4931fe2dbe1cc0e7d350a4b51b0b330e43971d98",
                    "status": "affected",
                    "version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "6adaa9fae36f848afa7278945d725e197e33c496",
                    "status": "affected",
                    "version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "453a6d2a68e54a483d67233c6e1e24c4095ee4be",
                    "status": "affected",
                    "version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "fs/smb/client/smb2ops.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.12"
                  },
                  {
                    "lessThan": "6.12",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.44",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.16.*",
                    "status": "unaffected",
                    "version": "6.16.4",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.17",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "14C4B269-8787-47B5-A04C-8BFCE8F9C2D8",
                    "versionEndExcluding": "6.12.44",
                    "versionStartIncluding": "6.12",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "AFC28995-B8C3-4B68-8CB6-78E792B6629D",
                    "versionEndExcluding": "6.16.4",
                    "versionStartIncluding": "6.13",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: Fix oops due to uninitialised variable\n\nFix smb3_init_transform_rq() to initialise buffer to NULL before calling\nnetfs_alloc_folioq_buffer() as netfs assumes it can append to the buffer it\nis given.  Setting it to NULL means it should start a fresh buffer, but the\nvalue is currently undefined."
          }
        ],
        "id": "CVE-2025-38737",
        "lastModified": "2026-07-30T06:23:38.967",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 9.8,
                "baseSeverity": "CRITICAL",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2025-09-05T18:15:43.090",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/453a6d2a68e54a483d67233c6e1e24c4095ee4be"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/4931fe2dbe1cc0e7d350a4b51b0b330e43971d98"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/6adaa9fae36f848afa7278945d725e197e33c496"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-908"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-30T09:02:42+00:00",
      "cve": "CVE-2025-38737",
      "id": "CVE-2025-38737",
      "initial_release_date": "2025-09-05T00:00:00+00:00",
      "product_status:fixed": "616",
      "product_status:known_not_affected": "198",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: cifs: Fix oops due to uninitialised variable",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38737.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-04T00:25:07Z",
      "cve": "CVE-2025-38737",
      "id": "CVE-2025-38737",
      "initial_release_date": "2025-09-05T23:23:23Z",
      "product_status:known_affected": "20",
      "product_status:known_not_affected": "540",
      "product_status:recommended": "42",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-38737",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-38737.json",
      "version": "22"
    }
  }
}



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.


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.