{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-22057", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-12-29T08:45:45.812Z", "datePublished": "2025-04-16T14:12:14.234Z", "dateUpdated": "2026-08-05T11:56:25.007Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:56:25.007Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: decrease cached dst counters in dst_release\n\nUpstream fix ac888d58869b (\"net: do not delay dst_entries_add() in\ndst_release()\") moved decrementing the dst count from dst_destroy to\ndst_release to avoid accessing already freed data in case of netns\ndismantle. However in case CONFIG_DST_CACHE is enabled and OvS+tunnels\nare used, this fix is incomplete as the same issue will be seen for\ncached dsts:\n\n Unable to handle kernel paging request at virtual address ffff5aabf6b5c000\n Call trace:\n percpu_counter_add_batch+0x3c/0x160 (P)\n dst_release+0xec/0x108\n dst_cache_destroy+0x68/0xd8\n dst_destroy+0x13c/0x168\n dst_destroy_rcu+0x1c/0xb0\n rcu_do_batch+0x18c/0x7d0\n rcu_core+0x174/0x378\n rcu_core_si+0x18/0x30\n\nFix this by invalidating the cache, and thus decrementing cached dst\ncounters, in dst_release too." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Triggering requires local configuration of a metadata tunnel (tc `action tunnel_key set`, nft tunnel object, or OVS set_tunnel) via netlink plus a network-namespace dismantle; received packets alone cannot populate the dst_cache since RX-allocated tun_dsts have no cache initialized.\nAC:L - The attacker controls both sides — they configure the cached tunnel dst and they trigger the netns teardown that frees the percpu counter — and `cleanup_net()` performs no rcu_barrier() between device-op exit (which queues dst_destroy_rcu) and ip6_route_net_exit(), so the window is wide and the whole sequence can be repeated in a loop until it lands.\nPR:L - tc actions, nftables tunnel objects, tunnel device creation and netns teardown are all gated by `netlink_net_capable(skb, CAP_NET_ADMIN)`, which checks against `sock_net(sk)->user_ns`, so an unprivileged local user obtains everything needed via `unshare -Urn`.\nUI:N - The attacker performs the entire sequence — namespace creation, tunnel/action setup, traffic generation, and namespace destruction — with no action by any other user.\nS:U - The use-after-free corrupts kernel memory within the same kernel security authority; no VM, IOMMU, or hypervisor boundary is crossed.\nC:H - `percpu_counter_add_batch()` reads freed percpu memory through the dangling `fbc->counters` pointer and folds that value into a kernel counter; per use-after-free scoring this yields potential disclosure of reclaimed kernel heap contents.\nI:H - The stale `this_cpu_write()` performs a use-after-free write into a freed percpu chunk that other percpu allocations can reclaim, corrupting unrelated kernel state (e.g. counters/refcounts) in an attacker-groomable way.\nA:H - The reported failure is a fatal kernel paging fault in `percpu_counter_add_batch()` from an RCU softirq callback, which panics or oopses the machine in unrecoverable context." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/dst.c" ], "versions": [ { "version": "d71785ffc7e7cae3fbdc4ea8a9d05b7a1c59f7b8", "lessThan": "ccc331fd5bcae131d2627d5ef099d4a1f6540aea", "status": "affected", "versionType": "git" }, { "version": "d71785ffc7e7cae3fbdc4ea8a9d05b7a1c59f7b8", "lessThan": "92a5c18513117be69bc00419dd1724c1940f8fcd", "status": "affected", "versionType": "git" }, { "version": "d71785ffc7e7cae3fbdc4ea8a9d05b7a1c59f7b8", "lessThan": "836415a8405c9665ae55352fc5ba865c242f5e4f", "status": "affected", "versionType": "git" }, { "version": "d71785ffc7e7cae3fbdc4ea8a9d05b7a1c59f7b8", "lessThan": "e833e7ad64eb2f63867f65303be49ca30ee8819e", "status": "affected", "versionType": "git" }, { "version": "d71785ffc7e7cae3fbdc4ea8a9d05b7a1c59f7b8", "lessThan": "3a0a3ff6593d670af2451ec363ccb7b18aec0c0a", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/dst.c" ], "versions": [ { "version": "4.6", "status": "affected" }, { "version": "0", "lessThan": "4.6", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.87", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.23", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.13.11", "lessThanOrEqual": "6.13.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.14.2", "lessThanOrEqual": "6.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15", "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": "4.6", "versionEndExcluding": "6.6.87" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.12.23" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.13.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.14.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.15" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ccc331fd5bcae131d2627d5ef099d4a1f6540aea" }, { "url": "https://git.kernel.org/stable/c/92a5c18513117be69bc00419dd1724c1940f8fcd" }, { "url": "https://git.kernel.org/stable/c/836415a8405c9665ae55352fc5ba865c242f5e4f" }, { "url": "https://git.kernel.org/stable/c/e833e7ad64eb2f63867f65303be49ca30ee8819e" }, { "url": "https://git.kernel.org/stable/c/3a0a3ff6593d670af2451ec363ccb7b18aec0c0a" } ], "title": "net: decrease cached dst counters in dst_release", "x_generator": { "engine": "bippy-1.2.0" } } } }