CVE-2025-39836 (GCVE-0-2025-39836)

Vulnerability from cvelistv5 – Published: 2025-09-16 13:08 – Updated: 2026-08-05 12:05
VLAI
Title
efi: stmm: Fix incorrect buffer allocation method
Summary
In the Linux kernel, the following vulnerability has been resolved: efi: stmm: Fix incorrect buffer allocation method The communication buffer allocated by setup_mm_hdr() is later on passed to tee_shm_register_kernel_buf(). The latter expects those buffers to be contiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause various corruptions or BUGs, specifically since commit 9aec2fb0fd5e ("slab: allocate frozen pages"), though it was broken before as well. Fix this by using alloc_pages_exact() instead of kmalloc().
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-14 18:18 UTC
CWE
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7034 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: c44b6be62e8dd4ee0a308c36a70620613e6fc55f , < 77ff27ff0e4529a003c8a1c2492c111968c378d3 (git)
Affected: c44b6be62e8dd4ee0a308c36a70620613e6fc55f , < 630c0e6064daf84f17aad1a7d9ca76b562e3fe47 (git)
Affected: c44b6be62e8dd4ee0a308c36a70620613e6fc55f , < c5e81e672699e0c5557b2b755cc8f7a69aa92bff (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.8
Unaffected: 0 , < 6.8 (semver)
Unaffected: 6.12.45 , ≤ 6.12.* (semver)
Unaffected: 6.16.5 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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                  "versionType": "git"
                },
                {
                  "lessThan": "c5e81e672699e0c5557b2b755cc8f7a69aa92bff",
                  "status": "affected",
                  "version": "c44b6be62e8dd4ee0a308c36a70620613e6fc55f",
                  "versionType": "git"
                }
              ]
            },
            {
              "defaultStatus": "affected",
              "product": "Linux",
              "programFiles": [
                "drivers/firmware/efi/stmm/tee_stmm_efi.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "status": "affected",
                  "version": "6.8"
                },
                {
                  "lessThan": "6.8",
                  "status": "unaffected",
                  "version": "0",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.12.*",
                  "status": "unaffected",
                  "version": "6.12.45",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.16.*",
                  "status": "unaffected",
                  "version": "6.16.5",
                  "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": "6.12.45",
                      "versionStartIncluding": "6.8",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.16.5",
                      "versionStartIncluding": "6.8",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.17",
                      "versionStartIncluding": "6.8",
                      "vulnerable": true
                    }
                  ],
                  "negate": false,
                  "operator": "OR"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nefi: stmm: Fix incorrect buffer allocation method\n\nThe communication buffer allocated by setup_mm_hdr() is later on passed\nto tee_shm_register_kernel_buf(). The latter expects those buffers to be\ncontiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause\nvarious corruptions or BUGs, specifically since commit 9aec2fb0fd5e\n(\"slab: allocate frozen pages\"), though it was broken before as well.\n\nFix this by using alloc_pages_exact() instead of kmalloc()."
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 7.8,
                "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"
              }
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-07-30T05:57:55.076Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/77ff27ff0e4529a003c8a1c2492c111968c378d3"
            },
            {
              "url": "https://git.kernel.org/stable/c/630c0e6064daf84f17aad1a7d9ca76b562e3fe47"
            },
            {
              "url": "https://git.kernel.org/stable/c/c5e81e672699e0c5557b2b755cc8f7a69aa92bff"
            }
          ],
          "title": "efi: stmm: Fix incorrect buffer allocation method",
          "x_generator": {
            "engine": "bippy-1.2.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2025-39836",
        "datePublished": "2025-09-16T13:08:52.326Z",
        "dateReserved": "2025-04-16T07:20:57.141Z",
        "dateUpdated": "2026-07-30T05:57:55.076Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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