{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43407", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:56.008Z", "datePublished": "2026-05-08T14:21:46.927Z", "dateUpdated": "2026-08-05T12:27:50.423Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:27:50.423Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: Fix potential out-of-bounds access in ceph_handle_auth_reply()\n\nThis patch fixes an out-of-bounds access in ceph_handle_auth_reply()\nthat can be triggered by a message of type CEPH_MSG_AUTH_REPLY. In\nceph_handle_auth_reply(), the value of the payload_len field of such a\nmessage is stored in a variable of type int. A value greater than\nINT_MAX leads to an integer overflow and is interpreted as a negative\nvalue. This leads to decrementing the pointer address by this value and\nsubsequently accessing it because ceph_decode_need() only checks that\nthe memory access does not exceed the end address of the allocation.\n\nThis patch fixes the issue by changing the data type of payload_len to\nu32. Additionally, the data type of result_msg_len is changed to u32,\nas it is also a variable holding a non-negative length.\n\nAlso, an additional layer of sanity checks is introduced, ensuring that\ndirectly after reading it from the message, payload_len and\nresult_msg_len are not greater than the overall segment length.\n\nBUG: KASAN: slab-out-of-bounds in ceph_handle_auth_reply+0x642/0x7a0 [libceph]\nRead of size 4 at addr ffff88811404df14 by task kworker/20:1/262\n\nCPU: 20 UID: 0 PID: 262 Comm: kworker/20:1 Not tainted 6.19.2 #5 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\nWorkqueue: ceph-msgr ceph_con_workfn [libceph]\nCall Trace:\n \n dump_stack_lvl+0x76/0xa0\n print_report+0xd1/0x620\n ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n ? kasan_complete_mode_report_info+0x72/0x210\n kasan_report+0xe7/0x130\n ? ceph_handle_auth_reply+0x642/0x7a0 [libceph]\n ? ceph_handle_auth_reply+0x642/0x7a0 [libceph]\n __asan_report_load_n_noabort+0xf/0x20\n ceph_handle_auth_reply+0x642/0x7a0 [libceph]\n mon_dispatch+0x973/0x23d0 [libceph]\n ? apparmor_socket_recvmsg+0x6b/0xa0\n ? __pfx_mon_dispatch+0x10/0x10 [libceph]\n ? __kasan_check_write+0x14/0x30i\n ? mutex_unlock+0x7f/0xd0\n ? __pfx_mutex_unlock+0x10/0x10\n ? __pfx_do_recvmsg+0x10/0x10 [libceph]\n ceph_con_process_message+0x1f1/0x650 [libceph]\n process_message+0x1e/0x450 [libceph]\n ceph_con_v2_try_read+0x2e48/0x6c80 [libceph]\n ? __pfx_ceph_con_v2_try_read+0x10/0x10 [libceph]\n ? save_fpregs_to_fpstate+0xb0/0x230\n ? raw_spin_rq_unlock+0x17/0xa0\n ? finish_task_switch.isra.0+0x13b/0x760\n ? __switch_to+0x385/0xda0\n ? __kasan_check_write+0x14/0x30\n ? mutex_lock+0x8d/0xe0\n ? __pfx_mutex_lock+0x10/0x10\n ceph_con_workfn+0x248/0x10c0 [libceph]\n process_one_work+0x629/0xf80\n ? __kasan_check_write+0x14/0x30\n worker_thread+0x87f/0x1570\n ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n ? __pfx_try_to_wake_up+0x10/0x10\n ? kasan_print_address_stack_frame+0x1f7/0x280\n ? __pfx_worker_thread+0x10/0x10\n kthread+0x396/0x830\n ? __pfx__raw_spin_lock_irq+0x10/0x10\n ? __pfx_kthread+0x10/0x10\n ? __kasan_check_write+0x14/0x30\n ? recalc_sigpending+0x180/0x210\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x3f7/0x610\n ? __pfx_ret_from_fork+0x10/0x10\n ? __switch_to+0x385/0xda0\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1a/0x30\n \n\n[ idryomov: replace if statements with ceph_decode_need() for\n payload_len and result_msg_len ]" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H", "baseScore": 9.1, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The vulnerable `CEPH_MSG_AUTH_REPLY` is parsed from data received over a Ceph messenger TCP connection from a monitor peer. A malicious or compromised monitor, or an attacker in position to impersonate one, can supply the crafted network message remotely.\nAC:L - The trigger is a deterministic malformed length field in a single auth reply, with no race or unusual heap state required to reach the out-of-bounds read. The attacker controls the relevant message contents.\nPR:N - The vulnerable reply is processed by the kernel client from the network peer during monitor/auth session handling, before any attacker-controlled credentials are required on the target. No local account or target privileges are needed.\nUI:N - Once a Ceph client connects or reconnects to the monitor peer, the attacker can send the crafted reply without further victim action. This is server-to-client network input processing.\nS:U - The impact is within the Linux kernel/client security authority. It does not cross a hypervisor, IOMMU, or separate authorization scope boundary.\nC:H - The signed length overflow lets the attacker move the decode pointer before the message buffer and perform an out-of-bounds kernel memory read at an attacker-influenced offset. Although the immediate read is small, it is not confined to a fixed in-object field, so high confidentiality impact is the safer defensible choice.\nI:N - The bug is an out-of-bounds read caused by pointer underflow; the investigated path does not provide an out-of-bounds write or direct memory corruption primitive. The downstream auth handlers reject the inverted buffer range or ignore the payload.\nA:H - The commit includes a KASAN slab-out-of-bounds report in `ceph_handle_auth_reply()`, and attacker-controlled pointer underflow can fault or oops the kernel worker processing the connection. A malicious peer can repeat the malformed reply to disrupt affected clients." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ceph/auth.c" ], "versions": [ { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "ea080b21092590122c3f971cf588932cdbf47847", "status": "affected", "versionType": "git" }, { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "edc678e5cd11730a2834b43071d8923f05bc334d", "status": "affected", "versionType": "git" }, { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "6cee34d6669fe176b4259131adb1a145c939b472", "status": "affected", "versionType": "git" }, { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "8bb87547e92dcf0928ed763c60e0ac8d733c3656", "status": "affected", "versionType": "git" }, { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "ed024d2f4c79c0eb2464df0fb640610ac301f9a0", "status": "affected", "versionType": "git" }, { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "f9da5c1bbac5c8e33259fe00ed7347438fffa969", "status": "affected", "versionType": "git" }, { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "9f9e2297f45fc2d2524eb104c289d69ddef95665", "status": "affected", "versionType": "git" }, { "version": "4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc", "lessThan": "b282c43ed156ae15ea76748fc15cd5c39dc9ab72", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ceph/auth.c" ], "versions": [ { "version": "2.6.34", "status": "affected" }, { "version": "0", "lessThan": "2.6.34", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.253", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.203", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.167", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.130", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.78", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.19", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.9", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "2.6.34", "versionEndExcluding": "5.10.253" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "5.15.203" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.1.167" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.6.130" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.12.78" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.18.19" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.19.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ea080b21092590122c3f971cf588932cdbf47847" }, { "url": "https://git.kernel.org/stable/c/edc678e5cd11730a2834b43071d8923f05bc334d" }, { "url": "https://git.kernel.org/stable/c/6cee34d6669fe176b4259131adb1a145c939b472" }, { "url": "https://git.kernel.org/stable/c/8bb87547e92dcf0928ed763c60e0ac8d733c3656" }, { "url": "https://git.kernel.org/stable/c/ed024d2f4c79c0eb2464df0fb640610ac301f9a0" }, { "url": "https://git.kernel.org/stable/c/f9da5c1bbac5c8e33259fe00ed7347438fffa969" }, { "url": "https://git.kernel.org/stable/c/9f9e2297f45fc2d2524eb104c289d69ddef95665" }, { "url": "https://git.kernel.org/stable/c/b282c43ed156ae15ea76748fc15cd5c39dc9ab72" } ], "title": "libceph: Fix potential out-of-bounds access in ceph_handle_auth_reply()", "x_generator": { "engine": "bippy-1.2.0" } } } }