Vulnerability-Lookup

GHSA-GRXX-H4MR-VFPG

Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-17 06:33

Details

In the Linux kernel, the following vulnerability has been resolved:

crypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one

Sashiko notes:

regarding the bounds check in snp_filter_reserved_mem_regions() called via walk_iomem_res_desc(): does the check if ((range_list->num_elements * 16 + 8) > PAGE_SIZE) allow an off-by-one heap buffer overflow?

If range_list->num_elements is 255, 255 * 16 + 8 = 4088, which is <= 4096. Writing range->base (8 bytes) fills 4088-4095, but writing range->page_count (4 bytes) would write to 4096-4099, overflowing the kzalloc-allocated PAGE_SIZE buffer.

Fix this by accounting for the entry about to be written to, in addition to the entries that are already allocated.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-74404"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-15T06:22:42Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one\n\nSashiko notes:\n\n\u003e regarding the bounds check in snp_filter_reserved_mem_regions()\n\u003e called via walk_iomem_res_desc(): does the check\n\u003e if ((range_list-\u003enum_elements * 16 + 8) \u003e PAGE_SIZE)\n\u003e allow an off-by-one heap buffer overflow?\n\u003e\n\u003e If range_list-\u003enum_elements is 255, 255 * 16 + 8 = 4088, which is \u003c= 4096.\n\u003e Writing range-\u003ebase (8 bytes) fills 4088-4095, but writing range-\u003epage_count\n\u003e (4 bytes) would write to 4096-4099, overflowing the kzalloc-allocated\n\u003e PAGE_SIZE buffer.\n\nFix this by accounting for the entry about to be written to, in addition to\nthe entries that are already allocated.",
  "id": "GHSA-grxx-h4mr-vfpg",
  "modified": "2026-08-17T06:33:43Z",
  "published": "2026-08-15T06:32:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74404"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1b864b6cb213bbd7b406e9b2e98c962077f300df"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/830c1f3e71989448652973375ef5e39b6ede47a3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/af7341616b742ad2c374a90998bd650a035f694d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c5c79d92da0f9a09f48be5e2aabed2d6d1a96294"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-74404 (GCVE-0-2026-74404)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:59 – Updated: 2026-08-17 05:46

Title

crypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one

Summary

In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one Sashiko notes: > regarding the bounds check in snp_filter_reserved_mem_regions() > called via walk_iomem_res_desc(): does the check > if ((range_list->num_elements * 16 + 8) > PAGE_SIZE) > allow an off-by-one heap buffer overflow? > > If range_list->num_elements is 255, 255 * 16 + 8 = 4088, which is <= 4096. > Writing range->base (8 bytes) fills 4088-4095, but writing range->page_count > (4 bytes) would write to 4096-4099, overflowing the kzalloc-allocated > PAGE_SIZE buffer. Fix this by accounting for the entry about to be written to, in addition to the entries that are already allocated.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/830c1f3e719894486…
https://git.kernel.org/stable/c/c5c79d92da0f9a09f…
https://git.kernel.org/stable/c/af7341616b742ad2c…
https://git.kernel.org/stable/c/1b864b6cb213bbd7b…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 1ca5614b84eed5904f65f143e0e7aaab0ac4c6b2 , < 830c1f3e71989448652973375ef5e39b6ede47a3 (git) Affected: 1ca5614b84eed5904f65f143e0e7aaab0ac4c6b2 , < c5c79d92da0f9a09f48be5e2aabed2d6d1a96294 (git) Affected: 1ca5614b84eed5904f65f143e0e7aaab0ac4c6b2 , < af7341616b742ad2c374a90998bd650a035f694d (git) Affected: 1ca5614b84eed5904f65f143e0e7aaab0ac4c6b2 , < 1b864b6cb213bbd7b406e9b2e98c962077f300df (git)
Linux	Linux	Affected: 6.9 Unaffected: 0 , < 6.9 (semver) Unaffected: 6.12.97 , ≤ 6.12.* (semver) Unaffected: 6.18.40 , ≤ 6.18.* (semver) Unaffected: 7.1.5 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/crypto/ccp/sev-dev.c"
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          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "830c1f3e71989448652973375ef5e39b6ede47a3",
              "status": "affected",
              "version": "1ca5614b84eed5904f65f143e0e7aaab0ac4c6b2",
              "versionType": "git"
            },
            {
              "lessThan": "c5c79d92da0f9a09f48be5e2aabed2d6d1a96294",
              "status": "affected",
              "version": "1ca5614b84eed5904f65f143e0e7aaab0ac4c6b2",
              "versionType": "git"
            },
            {
              "lessThan": "af7341616b742ad2c374a90998bd650a035f694d",
              "status": "affected",
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              "versionType": "git"
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            {
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              "status": "affected",
              "version": "1ca5614b84eed5904f65f143e0e7aaab0ac4c6b2",
              "versionType": "git"
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          ]
        },
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          "defaultStatus": "affected",
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          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.9"
            },
            {
              "lessThan": "6.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "6.9",
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one\n\nSashiko notes:\n\n\u003e regarding the bounds check in snp_filter_reserved_mem_regions()\n\u003e called via walk_iomem_res_desc(): does the check\n\u003e if ((range_list-\u003enum_elements * 16 + 8) \u003e PAGE_SIZE)\n\u003e allow an off-by-one heap buffer overflow?\n\u003e\n\u003e If range_list-\u003enum_elements is 255, 255 * 16 + 8 = 4088, which is \u003c= 4096.\n\u003e Writing range-\u003ebase (8 bytes) fills 4088-4095, but writing range-\u003epage_count\n\u003e (4 bytes) would write to 4096-4099, overflowing the kzalloc-allocated\n\u003e PAGE_SIZE buffer.\n\nFix this by accounting for the entry about to be written to, in addition to\nthe entries that are already allocated."
        }
      ],
      "metrics": [
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            "baseSeverity": "HIGH",
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            "version": "3.1"
          },
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            {
              "lang": "en",
              "value": "AV:L - The overflow is reached only via local host paths\u2014KVM VM ioctl KVM_SEV_INIT2 (sev_guest_init2\u2192sev_platform_init\u2192__sev_snp_init_locked) or kernel boot-time SEV-SNP platform init\u2014not through any network, Bluetooth, or physical bus handler.\nAC:L - Once on an AMD SEV-SNP host with SNP firmware \u22651.52, a caller can deterministically trigger SNP_INIT_EX initialization via KVM_SEV_INIT2; no race or attacker-uncontrollable timing is required, only a firmware memory map with \u2265256 matching reserved/ACPI/PMEM iomem regions.\nPR:L - Exploitation requires local hypervisor access to create an SNP-capable KVM VM and issue KVM_SEV_INIT2 (typical /dev/kvm or kvm-group hypervisor operator), not unauthenticated remote access; comparable KVM ioctl CVEs in this repo score this as low privilege rather than init-namespace root only.\nUI:N - No victim interaction is needed beyond the attacker (or boot sequence) invoking SNP platform initialization; the bug fires automatically while enumerating the system iomem map during SNP_INIT_EX setup.\nS:U - The corruption occurs in host kernel heap memory during hypervisor SEV-SNP platform initialization by a host-side caller; it is not a guest-to-host VM escape, IOMMU/DMA bypass, or cross-authority sandbox breakout.\nC:H - The off-by-one permits a 4-byte out-of-bounds write of page_count past a PAGE_SIZE kzalloc buffer, corrupting adjacent kmalloc slab memory in ways that can be leveraged for kernel information disclosure.\nI:H - A controlled heap buffer overflow (even 4 bytes) can corrupt adjacent kernel objects and be developed into arbitrary kernel memory writes or control-flow hijacking, satisfying high integrity impact per kernel OOB-write guidance.\nA:H - Heap metadata/object corruption during SNP_INIT_EX can cause kernel oops/panic or leave the host in a failed state, especially on confidential-computing servers where SNP initialization is on the critical boot/VM-launch path."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:46:46.485Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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        },
        {
          "url": "https://git.kernel.org/stable/c/af7341616b742ad2c374a90998bd650a035f694d"
        },
        {
          "url": "https://git.kernel.org/stable/c/1b864b6cb213bbd7b406e9b2e98c962077f300df"
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      ],
      "title": "crypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one",
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        "engine": "bippy-1.2.0"
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74404",
    "datePublished": "2026-08-15T05:59:14.073Z",
    "dateReserved": "2026-08-15T05:44:03.892Z",
    "dateUpdated": "2026-08-17T05:46:46.485Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

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GHSA-GRXX-H4MR-VFPG

CVE-2026-74404 (GCVE-0-2026-74404)

Tags

Sightings

Nomenclature