{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-53223", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.392Z", "datePublished": "2026-06-25T08:39:24.588Z", "dateUpdated": "2026-08-05T12:34:15.752Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:34:15.752Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: guard timestamp cmsgs to real error queue skbs\n\nskb_is_err_queue() treats PACKET_OUTGOING as the sole marker for an skb\nfrom sk_error_queue. That assumption is not true for AF_PACKET sockets:\noutgoing packet taps are also delivered to packet sockets with\nskb->pkt_type == PACKET_OUTGOING, but their skb->cb is owned by AF_PACKET\ninstead of struct sock_exterr_skb.\n\nIf such an skb is received with timestamping enabled, the generic\ntimestamp cmsg path can read AF_PACKET control-buffer state as\nsock_exterr_skb::opt_stats. With SO_RXQ_OVFL enabled, the packet drop\ncounter overlaps opt_stats. An odd drop count makes the path emit\nSCM_TIMESTAMPING_OPT_STATS with skb->len and skb->data. For non-linear\nskbs this copies past the linear head and can trigger hardened usercopy or\ndisclose adjacent heap contents.\n\nKeep skb_is_err_queue() local to net/socket.c, but make it verify that\nthe PACKET_OUTGOING marker is paired with the sock_rmem_free destructor\ninstalled by sock_queue_err_skb(). AF_PACKET receive skbs use normal\nreceive ownership and no longer pass as error-queue skbs, while legitimate\nsk_error_queue entries keep the PACKET_OUTGOING marker and sock_rmem_free\nownership." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "baseScore": 7.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable path is reached through local socket syscalls on an AF_PACKET socket, including setsockopt(), sending traffic that is tapped as PACKET_OUTGOING, and recvmsg(). Remote packets alone do not reach the bug without a local attacker-controlled packet socket.\nAC:L - The attacker controls the socket options, packet-socket receive queue pressure/drop count, and outgoing traffic needed to make the timestamp cmsg path run. No uncontrollable race or rare environmental condition is required for the highest-impact disclosure/crash scenario.\nPR:L - Creating AF_PACKET sockets requires CAP_NET_RAW in the governing user namespace. Because this capability can be obtained by an unprivileged local user in user/network namespaces on common deployments, this is Low rather than High.\nUI:N - No victim action is required after the attacker has local execution; the attacker can configure the socket and trigger recvmsg() themselves. The bug is not dependent on opening a file, mounting media, or other user-assisted behavior.\nS:U - The impact remains within the kernel and the local host security authority. It does not cross a hypervisor, VM, IOMMU, or other separate security scope boundary.\nC:H - The bogus SCM_TIMESTAMPING_OPT_STATS cmsg can copy skb->len bytes from skb->data even when the skb is non-linear, reading past the linear head. That can disclose adjacent kernel heap contents to userspace, which is a high confidentiality impact.\nI:N - The investigated bug is an out-of-bounds read/copy-to-user and misclassification of skb metadata, not a kernel write primitive. I found no direct modification of kernel memory or protected data.\nA:H - The same invalid copy can trigger hardened usercopy failures or kernel oops/panic on hardened deployments. The local attacker can repeat the trigger, so availability impact is High." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/net/sock.h", "net/core/skbuff.c", "net/socket.c" ], "versions": [ { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "24a0d548d3a765cd4558224e4f8e06e14cba26e3", "status": "affected", "versionType": "git" }, { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "71ff5cdd5da61d0438e902aa0fd68c28bc901abe", "status": "affected", "versionType": "git" }, { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "ad9a0374ee6d11048e1f74cd5180bad58b9848b4", "status": "affected", "versionType": "git" }, { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "b903e9b5629ec8dd6db92174070045bf81ad7060", "status": "affected", "versionType": "git" }, { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "e0665b2a8e90bb08bd205062c75662b502d31797", "status": "affected", "versionType": "git" }, { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "3dde4fb941fa5649ab809f6cd3e20e0c424a4e31", "status": "affected", "versionType": "git" }, { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "eb51a9ad3ceb01bc6c0fb608dbc856e03ee6f24a", "status": "affected", "versionType": "git" }, { "version": "8605330aac5a5785630aec8f64378a54891937cc", "lessThan": "1ee90b77b727df903033db873c75caac5c27ec98", "status": "affected", "versionType": "git" }, { "version": "cdaf15b43bd31003220cb080bcbbd57787a2fca9", "status": "affected", "versionType": "git" }, { "version": "4.10.14", "lessThan": "4.11", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/net/sock.h", "net/core/skbuff.c", "net/socket.c" ], "versions": [ { "version": "4.11", "status": "affected" }, { "version": "0", "lessThan": "4.11", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.259", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.176", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.143", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.94", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.36", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.13", "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": "4.11", "versionEndExcluding": "5.10.259" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.15.210" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.1.176" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.6.143" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.12.94" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.18.36" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "7.0.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "7.1" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10.14" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/24a0d548d3a765cd4558224e4f8e06e14cba26e3" }, { "url": "https://git.kernel.org/stable/c/71ff5cdd5da61d0438e902aa0fd68c28bc901abe" }, { "url": "https://git.kernel.org/stable/c/ad9a0374ee6d11048e1f74cd5180bad58b9848b4" }, { "url": "https://git.kernel.org/stable/c/b903e9b5629ec8dd6db92174070045bf81ad7060" }, { "url": "https://git.kernel.org/stable/c/e0665b2a8e90bb08bd205062c75662b502d31797" }, { "url": "https://git.kernel.org/stable/c/3dde4fb941fa5649ab809f6cd3e20e0c424a4e31" }, { "url": "https://git.kernel.org/stable/c/eb51a9ad3ceb01bc6c0fb608dbc856e03ee6f24a" }, { "url": "https://git.kernel.org/stable/c/1ee90b77b727df903033db873c75caac5c27ec98" } ], "title": "net: guard timestamp cmsgs to real error queue skbs", "x_generator": { "engine": "bippy-1.2.0" } } } }