{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64115", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.035Z", "datePublished": "2026-07-19T15:40:15.513Z", "dateUpdated": "2026-08-05T12:39:24.360Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:39:24.360Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/vmci: fix UAF when peer resets connection during handshake\n\nvmci_transport_recv_connecting_server() returned err = 0 for a peer\nRST in its default switch arm:\n\n\terr = pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST ? 0 : -EINVAL;\n\nThat made vmci_transport_recv_listen() skip vsock_remove_pending(),\nleaving the pending socket on the listener's pending_links with\nsk_state = TCP_CLOSE while destroy: still dropped the explicit\nreference taken before schedule_delayed_work().\n\nOne second later vsock_pending_work() observed is_pending=true and\nperformed full cleanup: vsock_remove_pending() then the two trailing\nsock_put(sk) calls -- the first reached refcount 0 and __sk_freed\nthe socket, and the second wrote into the freed object:\n\n BUG: KASAN: slab-use-after-free in refcount_warn_saturate\n Write of size 4 at addr ffff88800b1cac80 by task kworker\n Workqueue: events vsock_pending_work\n\nTreat peer RST like any other unexpected packet type (err = -EINVAL).\nAll destroy: arms now return err < 0, so vmci_transport_recv_listen()\nremoves pending from pending_links synchronously and\nvsock_pending_work() takes the is_pending=false / !rejected branch,\ndropping only its own work reference. This also closes the\nmulti-packet race Sashiko reported on v2: pending is removed from\nthe list before any subsequent packet can find it.\n\nThe pre-existing sk_acceptq_removed() gap on the err < 0 path of\nvmci_transport_recv_listen() that Sashiko also noted is not\nintroduced or changed by this patch.\n\nTested on lts-6.12.79 with KASAN: 52/100 unpatched -> 0/100 patched." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Exploitation requires local AF_VSOCK syscalls (connect/close) to drive VMCI control packets; per kernel CVSS guidance, vsock is scored Local even when the peer is a VM guest reaching a host listener.\nAC:L - The attacker controls both sides of the handshake race by initiating a connection and aborting it with RST during TCP_SYN_SENT; KASAN testing showed 52/100 repro without conditions outside attacker control.\nPR:L - Any unprivileged local user inside a VM (or on the same host) can open AF_VSOCK sockets and connect to a listening peer without CAP_NET_ADMIN or other elevated privileges.\nUI:N - Exploitation requires only a victim service with a bound/listening vsock socket, which is normal background operation; no interactive victim action is needed.\nS:C - In the most severe reasonable VMware deployment, an unprivileged guest VM triggers kernel memory corruption on the hypervisor host via VMCI vsock, crossing the guest-to-host virtualisation security boundary analogous to KVM/Xen VM escape.\nC:H - The bug is a slab use-after-free on struct sock; UAF on kernel heap objects enables arbitrary memory read primitives through controlled reuse of the freed socket structure.\nI:H - The UAF involves a write to a freed object's refcount field and corrupts kernel heap metadata, providing a foundation for arbitrary write and kernel code execution via heap grooming.\nA:H - The vulnerability reliably triggers kernel UAF detected by KASAN (refcount write to freed memory on a kworker), which causes kernel oops/panic and denial of host availability." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/vmw_vsock/vmci_transport.c" ], "versions": [ { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "1e19f08552b90070ed18bafb1763c78297823af6", "status": "affected", "versionType": "git" }, { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "1dd531e28f61edd286edc486ab068f135b5ae1eb", "status": "affected", "versionType": "git" }, { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "ecda37f8faab3220da199335e42564cb7a9ad145", "status": "affected", "versionType": "git" }, { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "cc27e989a5dfdfcfc1cca7c3be27a0c7532b46cb", "status": "affected", "versionType": "git" }, { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "47e63077605c6c2aa45b3df9847a8cdc1f1f6ef9", "status": "affected", "versionType": "git" }, { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "440447699c681e26ed58e9c309cad718270a18b4", "status": "affected", "versionType": "git" }, { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "9fe74e42914c851d68069713b7b917a9c33faf26", "status": "affected", "versionType": "git" }, { "version": "d021c344051af91f42c5ba9fdedc176740cbd238", "lessThan": "99e22ddf4edb63dc8382bc028af928056d3450cf", "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/vmw_vsock/vmci_transport.c" ], "versions": [ { "version": "3.9", "status": "affected" }, { "version": "0", "lessThan": "3.9", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.258", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.209", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.142", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.92", "lessThanOrEqual": "6.12.*", "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": "3.9", "versionEndExcluding": "5.10.258" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9", "versionEndExcluding": "5.15.209" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9", "versionEndExcluding": "6.6.142" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9", "versionEndExcluding": "6.12.92" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9", "versionEndExcluding": "6.18.34" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9", "versionEndExcluding": "7.0.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/1e19f08552b90070ed18bafb1763c78297823af6" }, { "url": "https://git.kernel.org/stable/c/1dd531e28f61edd286edc486ab068f135b5ae1eb" }, { "url": "https://git.kernel.org/stable/c/ecda37f8faab3220da199335e42564cb7a9ad145" }, { "url": "https://git.kernel.org/stable/c/cc27e989a5dfdfcfc1cca7c3be27a0c7532b46cb" }, { "url": "https://git.kernel.org/stable/c/47e63077605c6c2aa45b3df9847a8cdc1f1f6ef9" }, { "url": "https://git.kernel.org/stable/c/440447699c681e26ed58e9c309cad718270a18b4" }, { "url": "https://git.kernel.org/stable/c/9fe74e42914c851d68069713b7b917a9c33faf26" }, { "url": "https://git.kernel.org/stable/c/99e22ddf4edb63dc8382bc028af928056d3450cf" } ], "title": "vsock/vmci: fix UAF when peer resets connection during handshake", "x_generator": { 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