{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64122", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.036Z", "datePublished": "2026-07-19T15:40:20.446Z", "dateUpdated": "2026-08-05T12:39:28.664Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:39:28.664Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Fix use-after-free in mlx5e_tx_reporter_timeout_recover\n\nmlx5e_tx_reporter_timeout_recover() accesses sq->netdev after\nmlx5e_safe_reopen_channels() has torn down and freed the channel (and\nits embedded SQs). Replace the three sq->netdev references with\npriv->netdev which is safe because priv outlives channel teardown.\n\nThe netdev_err() call already used priv->netdev for this reason; make\nthe trylock/unlock and health_channel_eq_recover calls consistent.\n\nThis fixes the following KASAN splat:\n\n BUG: KASAN: use-after-free in mlx5e_tx_reporter_timeout_recover+0x1dd/0x360 [mlx5_core]\n Read of size 8 at addr ffff889860ed0b28 by task kworker/u113:2/5277\n\n Call Trace:\n mlx5e_tx_reporter_timeout_recover+0x1dd/0x360 [mlx5_core]\n devlink_health_reporter_recover+0xa2/0x150\n devlink_health_report+0x254/0x7c0\n mlx5e_reporter_tx_timeout+0x297/0x380 [mlx5_core]\n mlx5e_tx_timeout_work+0x109/0x170 [mlx5_core]\n process_one_work+0x677/0xf20\n worker_thread+0x51f/0xd90\n kthread+0x3a5/0x810\n ret_from_fork+0x208/0x400\n ret_from_fork_asm+0x1a/0x30" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The bug is reached from the mlx5e netdev TX-timeout watchdog recovery path on Mellanox ConnectX NICs deployed on internet-facing cloud/datacenter servers; remote peers generate outbound traffic that can stall TX queues and fire `ndo_tx_timeout`, leading to `mlx5e_tx_reporter_timeout_recover()` without any local syscall.\nAC:L - Once a TX timeout occurs, recovery is deterministic: `mlx5e_health_channel_eq_recover()` typically fails when no EQEs are pending, `mlx5e_safe_reopen_channels()` frees the embedded SQ, and the stale `sq->netdev` dereference in `netdev_unlock()` always follows on that fallback path rather than requiring a race the attacker cannot influence.\nPR:N - No capability checks or authentication gates exist on the TX-timeout → devlink health auto-recover call chain; an unauthenticated remote attacker who can send traffic to a host mlx5 interface can induce the watchdog/recovery sequence without root, CAP_NET_ADMIN, or user-namespace privileges.\nUI:N - Exploitation requires no victim user action such as mounting a filesystem or opening a file; it is triggered automatically by the kernel netdev watchdog and workqueue recovery once TX queues stall.\nS:U - Impact is confined to kernel memory corruption and privilege escalation within the same host kernel security authority; this is not a VM-guest-to-host escape, IOMMU bypass, or other cross-boundary scenario.\nC:H - The KASAN splat confirms an 8-byte use-after-free read of `sq->netdev` from freed channel/SQ memory; UAF on this structure pointer can be leveraged for arbitrary kernel memory disclosure via heap reuse and controlled reads through the corrupted `net_device` reference.\nI:H - The UAF supplies a controlled `struct net_device *` to `netdev_unlock()`, which performs `mutex_unlock()` on attacker-influenced freed memory, enabling heap spraying and memory corruption primitives that can be developed into arbitrary kernel write or code execution.\nA:H - Use-after-free in kernel TX recovery provably causes KASAN faults and can panic or oops the host during `netdev_unlock()` on freed SQ memory, producing complete loss of kernel availability on affected mlx5 systems." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/mellanox/mlx5/core/en/reporter_tx.c" ], "versions": [ { "version": "4329514c61abefe4961541b128c549b017bab5ad", "lessThan": "1604a2d68414aa4cc34faac0b7faa9c14455e8d3", "status": "affected", "versionType": "git" }, { "version": "83ac0304a2d77519dae1e54c9713cbe1aedf19c9", "lessThan": "152295aa7dc2c5e046606f7dadc84fce41136446", "status": "affected", "versionType": "git" }, { "version": "83ac0304a2d77519dae1e54c9713cbe1aedf19c9", "lessThan": "7d260c5d2d89eb2c8c528d54b576b3aae3e20231", "status": "affected", "versionType": "git" }, { "version": "63f9d5fb4d8040077df801ca3270e2f02d55e0d9", "status": "affected", "versionType": "git" }, { "version": "6.18.14", "lessThan": "6.18.34", "status": "affected", "versionType": "semver" }, { "version": "6.19.4", "lessThan": "6.20", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/mellanox/mlx5/core/en/reporter_tx.c" ], "versions": [ { "version": "7.0", "status": "affected" }, { "version": "0", "lessThan": "7.0", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.34", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.11", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.14", "versionEndExcluding": "6.18.34" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0", "versionEndExcluding": "7.0.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0", "versionEndExcluding": "7.1" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19.4" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/1604a2d68414aa4cc34faac0b7faa9c14455e8d3" }, { "url": "https://git.kernel.org/stable/c/152295aa7dc2c5e046606f7dadc84fce41136446" }, { "url": "https://git.kernel.org/stable/c/7d260c5d2d89eb2c8c528d54b576b3aae3e20231" } ], "title": "net/mlx5e: Fix use-after-free in mlx5e_tx_reporter_timeout_recover", "x_generator": { "engine": "bippy-1.2.0" } } } }