{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2023-53489", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2023-53489", "idYear": 2023, "status": "PUBLISHED", "publishedAt": "2025-10-01T11:45:41.304Z", "updatedAt": "2026-05-11T19:45:58.719Z", "importedAt": "2026-10-24T01:57:03.413Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.\n\nsyzkaller reported [0] memory leaks of an UDP socket and ZEROCOPY\nskbs. We can reproduce the problem with these sequences:\n\n sk = socket(AF_INET, SOCK_DGRAM, 0)\n sk.setsockopt(SOL_SOCKET, SO_TIMESTAMPING, SOF_TIMESTAMPING_TX_SOFTWARE)\n sk.setsockopt(SOL_SOCKET, SO_ZEROCOPY, 1)\n sk.sendto(b'', MSG_ZEROCOPY, ('127.0.0.1', 53))\n sk.close()\n\nsendmsg() calls msg_zerocopy_alloc(), which allocates a skb, sets\nskb->cb->ubuf.refcnt to 1, and calls sock_hold(). Here, struct\nubuf_info_msgzc indirectly holds a refcnt of the socket. When the\nskb is sent, __skb_tstamp_tx() clones it and puts the clone into\nthe socket's error queue with the TX timestamp.\n\nWhen the original skb is received locally, skb_copy_ubufs() calls\nskb_unclone(), and pskb_expand_head() increments skb->cb->ubuf.refcnt.\nThis additional count is decremented while freeing the skb, but struct\nubuf_info_msgzc still has a refcnt, so __msg_zerocopy_callback() is\nnot called.\n\nThe last refcnt is not released unless we retrieve the TX timestamped\nskb by recvmsg(). Since we clear the error queue in inet_sock_destruct()\nafter the socket's refcnt reaches 0, there is a circular dependency.\nIf we close() the socket holding such skbs, we never call sock_put()\nand leak the count, sk, and skb.\n\nTCP has the same problem, and commit e0c8bccd40fc (\"net: stream:\npurge sk_error_queue in sk_stream_kill_queues()\") tried to fix it\nby calling skb_queue_purge() during close(). However, there is a\nsmall chance that skb queued in a qdisc or device could be put\ninto the error queue after the skb_queue_purge() call.\n\nIn __skb_tstamp_tx(), the cloned skb should not have a reference\nto the ubuf to remove the circular dependency, but skb_clone() does\nnot call skb_copy_ubufs() for zerocopy skb. So, we need to call\nskb_orphan_frags_rx() for the cloned skb to call skb_copy_ubufs().\n\n[0]:\nBUG: memory leak\nunreferenced object 0xffff88800c6d2d00 (size 1152):\n comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n hex dump (first 32 bytes):\n 00 00 00 00 00 00 00 00 cd af e8 81 00 00 00 00 ................\n 02 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00 ...@............\n backtrace:\n [<0000000055636812>] sk_prot_alloc+0x64/0x2a0 net/core/sock.c:2024\n [<0000000054d77b7a>] sk_alloc+0x3b/0x800 net/core/sock.c:2083\n [<0000000066f3c7e0>] inet_create net/ipv4/af_inet.c:319 [inline]\n [<0000000066f3c7e0>] inet_create+0x31e/0xe40 net/ipv4/af_inet.c:245\n [<000000009b83af97>] __sock_create+0x2ab/0x550 net/socket.c:1515\n [<00000000b9b11231>] sock_create net/socket.c:1566 [inline]\n [<00000000b9b11231>] __sys_socket_create net/socket.c:1603 [inline]\n [<00000000b9b11231>] __sys_socket_create net/socket.c:1588 [inline]\n [<00000000b9b11231>] __sys_socket+0x138/0x250 net/socket.c:1636\n [<000000004fb45142>] __do_sys_socket net/socket.c:1649 [inline]\n [<000000004fb45142>] __se_sys_socket net/socket.c:1647 [inline]\n [<000000004fb45142>] __x64_sys_socket+0x73/0xb0 net/socket.c:1647\n [<0000000066999e0e>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n [<0000000066999e0e>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80\n [<0000000017f238c1>] entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nBUG: memory leak\nunreferenced object 0xffff888017633a00 (size 240):\n comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n hex dump (first 32 bytes):\n 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................\n 00 00 00 00 00 00 00 00 00 2d 6d 0c 80 88 ff ff .........-m.....\n backtrace:\n [<000000002b1c4368>] __alloc_skb+0x229/0x320 net/core/skbuff.c:497\n [<00000000143579a6>] alloc_skb include/linux/skbuff.h:1265 [inline]\n [<00000000143579a6>] sock_omalloc+0xaa/0x190 net/core/sock.c:2596\n [<00000000be626478>] msg_zerocopy_alloc net/core/skbuff.c:1294 [inline]\n [<00000000be626478>]\n---truncated---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "281072fb2a7294cde7acbf5375b879f40a8001b7" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "1f69c086b20e27763af28145981435423f088268" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "602fa8af44fd55a58f9e94eb673e8adad2c6cc46" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "230a5ed7d813fb516de81d23f09d7506753e41e9" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "43e4197dd5f6b474a8b16f8b6a42cd45cf4f9d1a" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "cb52e7f24c1d01a536a847dff0d1d95889cc3b5c" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "30290f210ba7426ff7592fe2eb4114b1b5bad219" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "426384dd4980040651536fef5feac4dcc4d7ee4e" }, { "version": "f214f915e7db99091f1312c48b30928c1e0c90b7", "status": "affected", "versionType": "git", "lessThan": "50749f2dd6854a41830996ad302aef2ffaf011d8" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.14", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.14" }, { "version": "4.14.315", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "4.14.*" }, { "version": "4.19.283", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "4.19.*" }, { "version": "5.4.243", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.4.*" }, { "version": "5.10.180", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.111", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.28", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.2.15", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.2.*" }, { "version": "6.3.2", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.3.*" }, { "version": "6.4", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }