{"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"}}}}