{"cve":"CVE-2026-53223","nvd":{"published":"2026-06-25T09:16:40.073","modified":"2026-10-19T20:19:10.460","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":7.1},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/1ee90b77b727df903033db873c75caac5c27ec98","https://git.kernel.org/stable/c/24a0d548d3a765cd4558224e4f8e06e14cba26e3","https://git.kernel.org/stable/c/3dde4fb941fa5649ab809f6cd3e20e0c424a4e31","https://git.kernel.org/stable/c/71ff5cdd5da61d0438e902aa0fd68c28bc901abe","https://git.kernel.org/stable/c/ad9a0374ee6d11048e1f74cd5180bad58b9848b4"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-53223","score":0.00136,"percentile":0.03027,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}