CVE-2026-23057 (GCVE-0-2026-23057)

Vulnerability from cvelistv5 – Published: 2026-02-04 16:07 – Updated: 2026-02-09 08:37
VLAI?
Title
vsock/virtio: Coalesce only linear skb
Summary
In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: Coalesce only linear skb vsock/virtio common tries to coalesce buffers in rx queue: if a linear skb (with a spare tail room) is followed by a small skb (length limited by GOOD_COPY_LEN = 128), an attempt is made to join them. Since the introduction of MSG_ZEROCOPY support, assumption that a small skb will always be linear is incorrect. In the zerocopy case, data is lost and the linear skb is appended with uninitialized kernel memory. Of all 3 supported virtio-based transports, only loopback-transport is affected. G2H virtio-transport rx queue operates on explicitly linear skbs; see virtio_vsock_alloc_linear_skb() in virtio_vsock_rx_fill(). H2G vhost-transport may allocate non-linear skbs, but only for sizes that are not considered for coalescence; see PAGE_ALLOC_COSTLY_ORDER in virtio_vsock_alloc_skb(). Ensure only linear skbs are coalesced. Note that skb_tailroom(last_skb) > 0 guarantees last_skb is linear.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 581512a6dc939ef122e49336626ae159f3b8a345 , < 568e9cd8ed7ca9bf748c7687ba6501f29d30e59f (git)
Affected: 581512a6dc939ef122e49336626ae159f3b8a345 , < 63ef9b300bd09e24c57050c5dbe68feedce42e72 (git)
Affected: 581512a6dc939ef122e49336626ae159f3b8a345 , < 0386bd321d0f95d041a7b3d7b07643411b044a96 (git)
Create a notification for this product.
    Linux Linux Affected: 6.7
Unaffected: 0 , < 6.7 (semver)
Unaffected: 6.12.68 , ≤ 6.12.* (semver)
Unaffected: 6.18.8 , ≤ 6.18.* (semver)
Unaffected: 6.19 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/vmw_vsock/virtio_transport_common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "568e9cd8ed7ca9bf748c7687ba6501f29d30e59f",
              "status": "affected",
              "version": "581512a6dc939ef122e49336626ae159f3b8a345",
              "versionType": "git"
            },
            {
              "lessThan": "63ef9b300bd09e24c57050c5dbe68feedce42e72",
              "status": "affected",
              "version": "581512a6dc939ef122e49336626ae159f3b8a345",
              "versionType": "git"
            },
            {
              "lessThan": "0386bd321d0f95d041a7b3d7b07643411b044a96",
              "status": "affected",
              "version": "581512a6dc939ef122e49336626ae159f3b8a345",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/vmw_vsock/virtio_transport_common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.7"
            },
            {
              "lessThan": "6.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.68",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.19",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.68",
                  "versionStartIncluding": "6.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.8",
                  "versionStartIncluding": "6.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19",
                  "versionStartIncluding": "6.7",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/virtio: Coalesce only linear skb\n\nvsock/virtio common tries to coalesce buffers in rx queue: if a linear skb\n(with a spare tail room) is followed by a small skb (length limited by\nGOOD_COPY_LEN = 128), an attempt is made to join them.\n\nSince the introduction of MSG_ZEROCOPY support, assumption that a small skb\nwill always be linear is incorrect. In the zerocopy case, data is lost and\nthe linear skb is appended with uninitialized kernel memory.\n\nOf all 3 supported virtio-based transports, only loopback-transport is\naffected. G2H virtio-transport rx queue operates on explicitly linear skbs;\nsee virtio_vsock_alloc_linear_skb() in virtio_vsock_rx_fill(). H2G\nvhost-transport may allocate non-linear skbs, but only for sizes that are\nnot considered for coalescence; see PAGE_ALLOC_COSTLY_ORDER in\nvirtio_vsock_alloc_skb().\n\nEnsure only linear skbs are coalesced. Note that skb_tailroom(last_skb) \u003e 0\nguarantees last_skb is linear."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-09T08:37:55.428Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/568e9cd8ed7ca9bf748c7687ba6501f29d30e59f"
        },
        {
          "url": "https://git.kernel.org/stable/c/63ef9b300bd09e24c57050c5dbe68feedce42e72"
        },
        {
          "url": "https://git.kernel.org/stable/c/0386bd321d0f95d041a7b3d7b07643411b044a96"
        }
      ],
      "title": "vsock/virtio: Coalesce only linear skb",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-23057",
    "datePublished": "2026-02-04T16:07:40.550Z",
    "dateReserved": "2026-01-13T15:37:45.951Z",
    "dateUpdated": "2026-02-09T08:37:55.428Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-23057\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-02-04T17:16:16.380\",\"lastModified\":\"2026-02-05T14:57:20.563\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nvsock/virtio: Coalesce only linear skb\\n\\nvsock/virtio common tries to coalesce buffers in rx queue: if a linear skb\\n(with a spare tail room) is followed by a small skb (length limited by\\nGOOD_COPY_LEN = 128), an attempt is made to join them.\\n\\nSince the introduction of MSG_ZEROCOPY support, assumption that a small skb\\nwill always be linear is incorrect. In the zerocopy case, data is lost and\\nthe linear skb is appended with uninitialized kernel memory.\\n\\nOf all 3 supported virtio-based transports, only loopback-transport is\\naffected. G2H virtio-transport rx queue operates on explicitly linear skbs;\\nsee virtio_vsock_alloc_linear_skb() in virtio_vsock_rx_fill(). H2G\\nvhost-transport may allocate non-linear skbs, but only for sizes that are\\nnot considered for coalescence; see PAGE_ALLOC_COSTLY_ORDER in\\nvirtio_vsock_alloc_skb().\\n\\nEnsure only linear skbs are coalesced. Note that skb_tailroom(last_skb) \u003e 0\\nguarantees last_skb is linear.\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0386bd321d0f95d041a7b3d7b07643411b044a96\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/568e9cd8ed7ca9bf748c7687ba6501f29d30e59f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/63ef9b300bd09e24c57050c5dbe68feedce42e72\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

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.