{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53088", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-05-02T15:51:43.551Z", "datePublished": "2025-05-02T15:55:34.840Z", "dateUpdated": "2026-08-05T09:12:43.438Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:12:43.438Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix UaF in listener shutdown\n\nAs reported by Christoph after having refactored the passive\nsocket initialization, the mptcp listener shutdown path is prone\nto an UaF issue.\n\n BUG: KASAN: use-after-free in _raw_spin_lock_bh+0x73/0xe0\n Write of size 4 at addr ffff88810cb23098 by task syz-executor731/1266\n\n CPU: 1 PID: 1266 Comm: syz-executor731 Not tainted 6.2.0-rc59af4eaa31c1f6c00c8f1e448ed99a45c66340dd5 #6\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n Call Trace:\n \n dump_stack_lvl+0x6e/0x91\n print_report+0x16a/0x46f\n kasan_report+0xad/0x130\n kasan_check_range+0x14a/0x1a0\n _raw_spin_lock_bh+0x73/0xe0\n subflow_error_report+0x6d/0x110\n sk_error_report+0x3b/0x190\n tcp_disconnect+0x138c/0x1aa0\n inet_child_forget+0x6f/0x2e0\n inet_csk_listen_stop+0x209/0x1060\n __mptcp_close_ssk+0x52d/0x610\n mptcp_destroy_common+0x165/0x640\n mptcp_destroy+0x13/0x80\n __mptcp_destroy_sock+0xe7/0x270\n __mptcp_close+0x70e/0x9b0\n mptcp_close+0x2b/0x150\n inet_release+0xe9/0x1f0\n __sock_release+0xd2/0x280\n sock_close+0x15/0x20\n __fput+0x252/0xa20\n task_work_run+0x169/0x250\n exit_to_user_mode_prepare+0x113/0x120\n syscall_exit_to_user_mode+0x1d/0x40\n do_syscall_64+0x48/0x90\n entry_SYSCALL_64_after_hwframe+0x72/0xdc\n\nThe msk grace period can legitly expire in between the last\nreference count dropped in mptcp_subflow_queue_clean() and\nthe later eventual access in inet_csk_listen_stop()\n\nAfter the previous patch we don't need anymore special-casing\nmsk listener socket cleanup: the mptcp worker will process each\nof the unaccepted msk sockets.\n\nJust drop the now unnecessary code.\n\nPlease note this commit depends on the two parent ones:\n\n mptcp: refactor passive socket initialization\n mptcp: use the workqueue to destroy unaccepted sockets" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is triggered by closing a local MPTCP listening socket that still has unaccepted connections; the entry path is socket/bind/listen/connect/close syscalls, not remote packet processing alone.\nAC:L - The attacker fully controls both the listener and the connecting peer and can force the close path that frees the msk then reuses it; the RCU window is schedulable (mutex between sock_put and inet_csk_listen_stop) and was reliably hit by syzkaller reproducers.\nPR:L - Creating and listening on IPPROTO_MPTCP sockets requires only an unprivileged local account (mptcp enabled by default; no CAP_* on the trigger path), including inside user/net namespaces.\nUI:N - Exploitation uses only the attacker's own sockets and close(); no victim action is required.\nS:U - This is a same-host kernel memory-corruption privilege-escalation class bug; impact stays within the kernel's security authority with no VM/IOMMU boundary crossed.\nC:H - The UAF targets a full mptcp/struct sock object in kmalloc-2k; after RCU free the attacker can reclaim and read through the dangling subflow->conn reference.\nI:H - Reclaiming the freed sock enables controlled writes and control-flow hijack via the subsequent subflow_error_report/mptcp_data_lock path on attacker-influenced memory.\nA:H - The UAF already produces a KASAN-detectable kernel write-after-free/oops on the spinlock path, so availability impact is a full kernel crash even without further exploitation." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/mptcp/protocol.c", "net/mptcp/protocol.h", "net/mptcp/subflow.c" ], "versions": [ { "version": "6aeed9045071f2252ff4e98fc13d1e304f33e5b0", "lessThan": "5564be74a22a61855f8b8c100d8c4abb003bb792", "status": "affected", "versionType": "git" }, { "version": "6aeed9045071f2252ff4e98fc13d1e304f33e5b0", "lessThan": "0f4f4cf5d32f10543deb946a37111e714579511e", "status": "affected", "versionType": "git" }, { "version": "6aeed9045071f2252ff4e98fc13d1e304f33e5b0", "lessThan": "0a3f4f1f9c27215e4ddcd312558342e57b93e518", "status": "affected", "versionType": "git" }, { "version": "a8a3e95c74e48c2c9b07b81fafda9122993f2e12", "status": "affected", "versionType": "git" }, { "version": "5.18.10", "lessThan": "5.19", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/mptcp/protocol.c", "net/mptcp/protocol.h", "net/mptcp/subflow.c" ], "versions": [ { "version": "5.19", "status": "affected" }, { "version": "0", "lessThan": "5.19", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.22", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.2.8", "lessThanOrEqual": "6.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.3", "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": "5.19", "versionEndExcluding": "6.1.22" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "6.2.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "6.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18.10" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/5564be74a22a61855f8b8c100d8c4abb003bb792" }, { "url": "https://git.kernel.org/stable/c/0f4f4cf5d32f10543deb946a37111e714579511e" }, { "url": "https://git.kernel.org/stable/c/0a3f4f1f9c27215e4ddcd312558342e57b93e518" } ], "title": "mptcp: fix UaF in listener shutdown", "x_generator": { "engine": "bippy-1.2.0" } } } }