Vulnerability-Lookup

CVE-2026-99079 (GCVE-0-2026-99079)

Vulnerability from cvelistv5 – Published: 2026-10-23 12:23 – Updated: 2026-10-24 14:10

Title

net/mlx5e: Prevent stale XSK buffer release on refill retry

Summary

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Prevent stale XSK buffer release on refill retry When an XDP redirect to an AF_XDP socket fails because its RX ring is full, the XSK core frees the buffer. During the subsequent batched refill of a legacy cyclic RQ, mlx5e also releases the WQE's XSK buffer before allocating a replacement. If that refill succeeds only partially, a WQE left without a replacement retains its old buffer pointer. The buffer can meanwhile be allocated to another WQE. A later refill retry can then free the live buffer through the stale pointer and publish the same UMEM frame twice. Mark the WQE as released immediately after the driver-side free. The flag is already cleared when a replacement buffer is assigned, so refill retries no longer release stale pointers. The failure is silent and produces no kernel warning or splat. A standalone legacy cyclic-RQ zero-copy libxsk reproducer, using 64-byte UDP traffic offered at 12 Mpps, detected it: stock stopped after 2,854,914 packets in 4.094 seconds, with 4,542 xdp_rx_ring_full events and 64 ownership/double-publication errors. With this change it processed 356,904,225 packets in 30 seconds despite 571,405 xdp_rx_ring_full events, with no ownership or data errors.

Severity

9.8 (Critical)


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

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7056 records in the last 180 days details

References

5 references

URL	Tags
https://git.kernel.org/stable/c/32bbb870078d46747…
https://git.kernel.org/stable/c/34d1db2b18e1c1d18…
https://git.kernel.org/stable/c/639522e5056cade57…
https://git.kernel.org/stable/c/655f47477054d19de…
https://git.kernel.org/stable/c/e01620844c5c88b6f…

Impacted products

2 products

Vendor	Product	Version	CPE status
Linux	Linux	Affected: 3f93f82988bc6b4104314bf9aa485d47fbb7e241 , < 32bbb870078d467479965c21bbc4960c57eea208 (git) Affected: 3f93f82988bc6b4104314bf9aa485d47fbb7e241 , < 34d1db2b18e1c1d189e34dd51923e031815f88e3 (git) Affected: 3f93f82988bc6b4104314bf9aa485d47fbb7e241 , < 639522e5056cade578a324acfa993ec6c9f7f5dc (git) Affected: 3f93f82988bc6b4104314bf9aa485d47fbb7e241 , < 655f47477054d19de3b138840be229a1a4490d0c (git) Affected: 3f93f82988bc6b4104314bf9aa485d47fbb7e241 , < e01620844c5c88b6fcf819d171df8e3976a0e76f (git)	guessed
Linux	Linux	Affected: 6.4 Unaffected: 0 , < 6.4 (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.113 , ≤ 6.12.* (semver) Unaffected: 6.18.57 , ≤ 6.18.* (semver) Unaffected: 7.2.11 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)	guessed

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ethernet/mellanox/mlx5/core/en_rx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "32bbb870078d467479965c21bbc4960c57eea208",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "34d1db2b18e1c1d189e34dd51923e031815f88e3",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "639522e5056cade578a324acfa993ec6c9f7f5dc",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "655f47477054d19de3b138840be229a1a4490d0c",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "e01620844c5c88b6fcf819d171df8e3976a0e76f",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ethernet/mellanox/mlx5/core/en_rx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.4"
            },
            {
              "lessThan": "6.4",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.57",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.160",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.113",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.57",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.11",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Prevent stale XSK buffer release on refill retry\n\nWhen an XDP redirect to an AF_XDP socket fails because its RX ring is\nfull, the XSK core frees the buffer. During the subsequent batched refill\nof a legacy cyclic RQ, mlx5e also releases the WQE\u0027s XSK buffer before\nallocating a replacement. If that refill succeeds only partially, a WQE\nleft without a replacement retains its old buffer pointer.\n\nThe buffer can meanwhile be allocated to another WQE. A later refill\nretry can then free the live buffer through the stale pointer and publish\nthe same UMEM frame twice.\n\nMark the WQE as released immediately after the driver-side free. The flag\nis already cleared when a replacement buffer is assigned, so refill\nretries no longer release stale pointers.\n\nThe failure is silent and produces no kernel warning or splat. A\nstandalone legacy cyclic-RQ zero-copy libxsk reproducer, using 64-byte UDP\ntraffic offered at 12 Mpps, detected it: stock stopped after 2,854,914\npackets in 4.094 seconds, with 4,542 xdp_rx_ring_full events and 64\nownership/double-publication errors. With this change it processed\n356,904,225 packets in 30 seconds despite 571,405 xdp_rx_ring_full events,\nwith no ownership or data errors."
        }
      ],
      "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 - UDP datagrams reaching mlx5 drive mlx5e_completion_event() -\u003e mlx5e_napi_poll() -\u003e mlx5e_poll_rx_cq()/XDP redirect, then mlx5e_napi_xsk_post() -\u003e mlx5e_post_rx_wqes() -\u003e patched mlx5e_xsk_free_rx_wqe(); sustained routable traffic fills the XSK RX ring and triggers stale release.\nAC:L - A sender can sustain small-packet traffic until __xsk_rcv_zc() reports RX-ring-full and mlx5e_xsk_alloc_rx_wqes_batched() refills only part of the missing WQEs; retries are deterministic and require no uncontrolled race or memory layout.\nPR:N - The NIC-CQE/NAPI receive path contains no capability or authentication check; xsk_create()\u0027s CAP_NET_RAW check applies to victim-side AF_XDP provisioning, while the remote UDP sender needs no privileges.\nUI:N - Once the zero-copy XSK pool and XDP redirect are active, xsk_rcv_zc() failure, mlx5e_napi_xsk_post(), and refill retries occur automatically as packets arrive, without further victim action.\nS:U - mlx5e_xsk_free_rx_wqe() corrupts the host kernel\u0027s xsk_buff_pool and mlx5 receive state without crossing a VM, IOMMU, or other security-authority boundary.\nC:H - Duplicate xdp_buff_xsk ownership lets repeated successful __xsk_rcv_zc() calls invoke unbounded xp_release(); in unaligned-UMEM mode, free_heads_cnt can write kernel pointers past the flexible free_heads[] array, yielding heap corruption exploitable for arbitrary disclosure.\nI:H - The duplicate WQEs can make xp_release() write beyond free_heads[], while xp_get_xskb() later trusts pointers popped through the corrupted count; this supplies out-of-bounds and corrupted-pointer write primitives capable of control-flow hijacking.\nA:H - The free_heads[] overflow or a bogus xskb consumed by xp_get_xskb() can oops or panic; additionally, the dma_dev_need_sync refill path can store NULL on allocation failure and have the stale retry pass it to xsk_buff_free()."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-24T14:10:21.247Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/32bbb870078d467479965c21bbc4960c57eea208"
        },
        {
          "url": "https://git.kernel.org/stable/c/34d1db2b18e1c1d189e34dd51923e031815f88e3"
        },
        {
          "url": "https://git.kernel.org/stable/c/639522e5056cade578a324acfa993ec6c9f7f5dc"
        },
        {
          "url": "https://git.kernel.org/stable/c/655f47477054d19de3b138840be229a1a4490d0c"
        },
        {
          "url": "https://git.kernel.org/stable/c/e01620844c5c88b6fcf819d171df8e3976a0e76f"
        }
      ],
      "title": "net/mlx5e: Prevent stale XSK buffer release on refill retry",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-99079",
    "datePublished": "2026-10-23T12:23:26.458Z",
    "dateReserved": "2026-09-25T10:25:14.389Z",
    "dateUpdated": "2026-10-24T14:10:21.247Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-99079",
      "date": "2026-10-24",
      "epss": "0.00209",
      "percentile": "0.10498"
    },
    "microsoft_vex": {
      "current_release_date": "2026-10-25T01:06:45.000Z",
      "cve": "CVE-2026-99079",
      "id": "msrc_CVE-2026-99079",
      "initial_release_date": "2026-10-25T01:05:18.000Z",
      "product_status:under_investigation": "2",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "net/mlx5e: Prevent stale XSK buffer release on refill retry",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-99079.json",
      "version": "2"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "drivers/net/ethernet/mellanox/mlx5/core/en_rx.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "32bbb870078d467479965c21bbc4960c57eea208",
                    "status": "affected",
                    "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "34d1db2b18e1c1d189e34dd51923e031815f88e3",
                    "status": "affected",
                    "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "639522e5056cade578a324acfa993ec6c9f7f5dc",
                    "status": "affected",
                    "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "655f47477054d19de3b138840be229a1a4490d0c",
                    "status": "affected",
                    "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "e01620844c5c88b6fcf819d171df8e3976a0e76f",
                    "status": "affected",
                    "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "drivers/net/ethernet/mellanox/mlx5/core/en_rx.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.4"
                  },
                  {
                    "lessThan": "6.4",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.160",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.113",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.57",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.2.*",
                    "status": "unaffected",
                    "version": "7.2.11",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.3",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Prevent stale XSK buffer release on refill retry\n\nWhen an XDP redirect to an AF_XDP socket fails because its RX ring is\nfull, the XSK core frees the buffer. During the subsequent batched refill\nof a legacy cyclic RQ, mlx5e also releases the WQE\u0027s XSK buffer before\nallocating a replacement. If that refill succeeds only partially, a WQE\nleft without a replacement retains its old buffer pointer.\n\nThe buffer can meanwhile be allocated to another WQE. A later refill\nretry can then free the live buffer through the stale pointer and publish\nthe same UMEM frame twice.\n\nMark the WQE as released immediately after the driver-side free. The flag\nis already cleared when a replacement buffer is assigned, so refill\nretries no longer release stale pointers.\n\nThe failure is silent and produces no kernel warning or splat. A\nstandalone legacy cyclic-RQ zero-copy libxsk reproducer, using 64-byte UDP\ntraffic offered at 12 Mpps, detected it: stock stopped after 2,854,914\npackets in 4.094 seconds, with 4,542 xdp_rx_ring_full events and 64\nownership/double-publication errors. With this change it processed\n356,904,225 packets in 30 seconds despite 571,405 xdp_rx_ring_full events,\nwith no ownership or data errors."
          }
        ],
        "id": "CVE-2026-99079",
        "lastModified": "2026-10-24T14:16:54.940",
        "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"
            }
          ]
        },
        "published": "2026-10-23T13:17:32.040",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/32bbb870078d467479965c21bbc4960c57eea208"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/34d1db2b18e1c1d189e34dd51923e031815f88e3"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/639522e5056cade578a324acfa993ec6c9f7f5dc"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/655f47477054d19de3b138840be229a1a4490d0c"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/e01620844c5c88b6fcf819d171df8e3976a0e76f"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    }
  }
}

FKIE_CVE-2026-99079

Vulnerability from fkie_nvd - Published: 2026-10-23 13:17 - Updated: 2026-10-24 14:16

Severity

9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Summary

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/32bbb870078d467479965c21bbc4960c57eea208
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/34d1db2b18e1c1d189e34dd51923e031815f88e3
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/639522e5056cade578a324acfa993ec6c9f7f5dc
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/655f47477054d19de3b138840be229a1a4490d0c
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e01620844c5c88b6fcf819d171df8e3976a0e76f

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ethernet/mellanox/mlx5/core/en_rx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "32bbb870078d467479965c21bbc4960c57eea208",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "34d1db2b18e1c1d189e34dd51923e031815f88e3",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "639522e5056cade578a324acfa993ec6c9f7f5dc",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "655f47477054d19de3b138840be229a1a4490d0c",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            },
            {
              "lessThan": "e01620844c5c88b6fcf819d171df8e3976a0e76f",
              "status": "affected",
              "version": "3f93f82988bc6b4104314bf9aa485d47fbb7e241",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ethernet/mellanox/mlx5/core/en_rx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.4"
            },
            {
              "lessThan": "6.4",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.57",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Prevent stale XSK buffer release on refill retry\n\nWhen an XDP redirect to an AF_XDP socket fails because its RX ring is\nfull, the XSK core frees the buffer. During the subsequent batched refill\nof a legacy cyclic RQ, mlx5e also releases the WQE\u0027s XSK buffer before\nallocating a replacement. If that refill succeeds only partially, a WQE\nleft without a replacement retains its old buffer pointer.\n\nThe buffer can meanwhile be allocated to another WQE. A later refill\nretry can then free the live buffer through the stale pointer and publish\nthe same UMEM frame twice.\n\nMark the WQE as released immediately after the driver-side free. The flag\nis already cleared when a replacement buffer is assigned, so refill\nretries no longer release stale pointers.\n\nThe failure is silent and produces no kernel warning or splat. A\nstandalone legacy cyclic-RQ zero-copy libxsk reproducer, using 64-byte UDP\ntraffic offered at 12 Mpps, detected it: stock stopped after 2,854,914\npackets in 4.094 seconds, with 4,542 xdp_rx_ring_full events and 64\nownership/double-publication errors. With this change it processed\n356,904,225 packets in 30 seconds despite 571,405 xdp_rx_ring_full events,\nwith no ownership or data errors."
    }
  ],
  "id": "CVE-2026-99079",
  "lastModified": "2026-10-24T14:16:54.940",
  "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"
      }
    ]
  },
  "published": "2026-10-23T13:17:32.040",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/32bbb870078d467479965c21bbc4960c57eea208"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/34d1db2b18e1c1d189e34dd51923e031815f88e3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/639522e5056cade578a324acfa993ec6c9f7f5dc"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/655f47477054d19de3b138840be229a1a4490d0c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e01620844c5c88b6fcf819d171df8e3976a0e76f"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

GHSA-7W5X-75MG-QR73

Vulnerability from github – Published: 2026-10-23 15:31 – Updated: 2026-10-24 15:32

Details

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

net/mlx5e: Prevent stale XSK buffer release on refill retry

When an XDP redirect to an AF_XDP socket fails because its RX ring is full, the XSK core frees the buffer. During the subsequent batched refill of a legacy cyclic RQ, mlx5e also releases the WQE's XSK buffer before allocating a replacement. If that refill succeeds only partially, a WQE left without a replacement retains its old buffer pointer.

The buffer can meanwhile be allocated to another WQE. A later refill retry can then free the live buffer through the stale pointer and publish the same UMEM frame twice.

Mark the WQE as released immediately after the driver-side free. The flag is already cleared when a replacement buffer is assigned, so refill retries no longer release stale pointers.

The failure is silent and produces no kernel warning or splat. A standalone legacy cyclic-RQ zero-copy libxsk reproducer, using 64-byte UDP traffic offered at 12 Mpps, detected it: stock stopped after 2,854,914 packets in 4.094 seconds, with 4,542 xdp_rx_ring_full events and 64 ownership/double-publication errors. With this change it processed 356,904,225 packets in 30 seconds despite 571,405 xdp_rx_ring_full events, with no ownership or data errors.

Severity

9.8 (Critical)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-99079"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-23T13:17:32Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Prevent stale XSK buffer release on refill retry\n\nWhen an XDP redirect to an AF_XDP socket fails because its RX ring is\nfull, the XSK core frees the buffer. During the subsequent batched refill\nof a legacy cyclic RQ, mlx5e also releases the WQE\u0027s XSK buffer before\nallocating a replacement. If that refill succeeds only partially, a WQE\nleft without a replacement retains its old buffer pointer.\n\nThe buffer can meanwhile be allocated to another WQE. A later refill\nretry can then free the live buffer through the stale pointer and publish\nthe same UMEM frame twice.\n\nMark the WQE as released immediately after the driver-side free. The flag\nis already cleared when a replacement buffer is assigned, so refill\nretries no longer release stale pointers.\n\nThe failure is silent and produces no kernel warning or splat. A\nstandalone legacy cyclic-RQ zero-copy libxsk reproducer, using 64-byte UDP\ntraffic offered at 12 Mpps, detected it: stock stopped after 2,854,914\npackets in 4.094 seconds, with 4,542 xdp_rx_ring_full events and 64\nownership/double-publication errors. With this change it processed\n356,904,225 packets in 30 seconds despite 571,405 xdp_rx_ring_full events,\nwith no ownership or data errors.",
  "id": "GHSA-7w5x-75mg-qr73",
  "modified": "2026-10-24T15:32:51Z",
  "published": "2026-10-23T15:31:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99079"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/32bbb870078d467479965c21bbc4960c57eea208"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/34d1db2b18e1c1d189e34dd51923e031815f88e3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/639522e5056cade578a324acfa993ec6c9f7f5dc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/655f47477054d19de3b138840be229a1a4490d0c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e01620844c5c88b6fcf819d171df8e3976a0e76f"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

MSRC_CVE-2026-99079

Vulnerability from csaf_microsoft - Published: 2026-10-25 01:05 - Updated: 2026-10-25 01:06

Summary

net/mlx5e: Prevent stale XSK buffer release on refill retry

Scope

1 vulnerability in this advisory, including CVE-2026-99079.

CVE-2026-99079

Under investigation: 2 products

Open the full advisory

Sightings

Author	Source	Type	Date	Other

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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.

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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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CVE-2026-99079 (GCVE-0-2026-99079)

FKIE_CVE-2026-99079

GHSA-7W5X-75MG-QR73

MSRC_CVE-2026-99079

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