{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-68341", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-16T14:48:05.298Z", "datePublished": "2025-12-23T13:58:26.749Z", "dateUpdated": "2026-08-05T12:10:57.506Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:10:57.506Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nveth: reduce XDP no_direct return section to fix race\n\nAs explain in commit fa349e396e48 (\"veth: Fix race with AF_XDP exposing\nold or uninitialized descriptors\") for veth there is a chance after\nnapi_complete_done() that another CPU can manage start another NAPI\ninstance running veth_pool(). For NAPI this is correctly handled as the\nnapi_schedule_prep() check will prevent multiple instances from getting\nscheduled, but for the remaining code in veth_pool() this can run\nconcurrent with the newly started NAPI instance.\n\nThe problem/race is that xdp_clear_return_frame_no_direct() isn't\ndesigned to be nested.\n\nPrior to commit 401cb7dae813 (\"net: Reference bpf_redirect_info via\ntask_struct on PREEMPT_RT.\") the temporary BPF net context\nbpf_redirect_info was stored per CPU, where this wasn't an issue. Since\nthis commit the BPF context is stored in 'current' task_struct. When\nrunning veth in threaded-NAPI mode, then the kthread becomes the storage\narea. Now a race exists between two concurrent veth_pool() function calls\none exiting NAPI and one running new NAPI, both using the same BPF net\ncontext.\n\nRace is when another CPU gets within the xdp_set_return_frame_no_direct()\nsection before exiting veth_pool() calls the clear-function\nxdp_clear_return_frame_no_direct()." } ], "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 - Unauthenticated packets received by a physical NIC can be XDP-redirected through a veth into the vulnerable threaded-NAPI path; no local access is needed to supply or time those packets.\nAC:L - Once veth XDP and threaded NAPI are configured, an attacker can repeatedly create the completion/rescheduling race using sustained or paced packet traffic.\nPR:N - The XDP topology requires administrative setup, but subsequent packet processing has no authentication or capability check, and the remote attacker needs no privileges.\nUI:N - Packets automatically traverse NIC XDP, veth queuing, threaded NAPI polling, and page return without victim interaction.\nS:U - The resulting memory corruption affects the host kernel within its existing security authority and does not inherently cross a VM, IOMMU, or equivalent boundary.\nC:H - The premature flag clear permits concurrent lockless page-pool recycling, potentially duplicating or stale-reusing pages and causing UAF-class corruption capable of exposing arbitrary kernel memory.\nI:H - The page-pool corruption can hand out a page multiple times and enable attacker-influenced writes into reused memory, making arbitrary writes or control-flow compromise defensible.\nA:H - Production failures resembling use-after-free were reported, and corrupted or multiply reused page-pool pages can cause kernel faults, panic, or persistent packet-processing failure." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/veth.c" ], "versions": [ { "version": "401cb7dae8130fd34eb84648e02ab4c506df7d5e", "lessThan": "c1ceabcb347d1b0f7e70a7384ec7eff3847b7628", "status": "affected", "versionType": "git" }, { "version": "401cb7dae8130fd34eb84648e02ab4c506df7d5e", "lessThan": "d0bd018ad72a8a598ae709588934135017f8af52", "status": "affected", "versionType": "git" }, { "version": "401cb7dae8130fd34eb84648e02ab4c506df7d5e", "lessThan": "a14602fcae17a3f1cb8a8521bedf31728f9e7e39", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/veth.c" ], "versions": [ { "version": "6.11", "status": "affected" }, { "version": "0", "lessThan": "6.11", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.61", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.11", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18", "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": "6.11", "versionEndExcluding": "6.12.61" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.17.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.18" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c1ceabcb347d1b0f7e70a7384ec7eff3847b7628" }, { "url": "https://git.kernel.org/stable/c/d0bd018ad72a8a598ae709588934135017f8af52" }, { "url": "https://git.kernel.org/stable/c/a14602fcae17a3f1cb8a8521bedf31728f9e7e39" } ], "title": "veth: reduce XDP no_direct return section to fix race", "x_generator": { "engine": "bippy-1.2.0" } } } }