Search Results (2262 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2024-56742 1 Linux 1 Linux Kernel 2026-10-30 3.3 Low
In the Linux kernel, the following vulnerability has been resolved: vfio/mlx5: Fix an unwind issue in mlx5vf_add_migration_pages() Fix an unwind issue in mlx5vf_add_migration_pages(). If a set of pages is allocated but fails to be added to the SG table, they need to be freed to prevent a memory leak. Any pages successfully added to the SG table will be freed as part of mlx5vf_free_data_buffer().
CVE-2024-56729 2 Linux, Redhat 2 Linux Kernel, Enterprise Linux 2026-10-30 4.7 Medium
In the Linux kernel, the following vulnerability has been resolved: smb: Initialize cfid->tcon before performing network ops Avoid leaking a tcon ref when a lease break races with opening the cached directory. Processing the leak break might take a reference to the tcon in cached_dir_lease_break() and then fail to release the ref in cached_dir_offload_close, since cfid->tcon is still NULL.
CVE-2024-56712 1 Linux 1 Linux Kernel 2026-10-30 3.3 Low
In the Linux kernel, the following vulnerability has been resolved: udmabuf: fix memory leak on last export_udmabuf() error path In export_udmabuf(), if dma_buf_fd() fails because the FD table is full, a dma_buf owning the udmabuf has already been created; but the error handling in udmabuf_create() will tear down the udmabuf without doing anything about the containing dma_buf. This leaves a dma_buf in memory that contains a dangling pointer; though that doesn't seem to lead to anything bad except a memory leak. Fix it by moving the dma_buf_fd() call out of export_udmabuf() so that we can give it different error handling. Note that the shape of this code changed a lot in commit 5e72b2b41a21 ("udmabuf: convert udmabuf driver to use folios"); but the memory leak seems to have existed since the introduction of udmabuf.
CVE-2024-56566 2 Linux, Redhat 2 Linux Kernel, Enterprise Linux 2026-10-30 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: mm/slub: Avoid list corruption when removing a slab from the full list Boot with slub_debug=UFPZ. If allocated object failed in alloc_consistency_checks, all objects of the slab will be marked as used, and then the slab will be removed from the partial list. When an object belonging to the slab got freed later, the remove_full() function is called. Because the slab is neither on the partial list nor on the full list, it eventually lead to a list corruption (actually a list poison being detected). So we need to mark and isolate the slab page with metadata corruption, do not put it back in circulation. Because the debug caches avoid all the fastpaths, reusing the frozen bit to mark slab page with metadata corruption seems to be fine. [ 4277.385669] list_del corruption, ffffea00044b3e50->next is LIST_POISON1 (dead000000000100) [ 4277.387023] ------------[ cut here ]------------ [ 4277.387880] kernel BUG at lib/list_debug.c:56! [ 4277.388680] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 4277.389562] CPU: 5 PID: 90 Comm: kworker/5:1 Kdump: loaded Tainted: G OE 6.6.1-1 #1 [ 4277.392113] Workqueue: xfs-inodegc/vda1 xfs_inodegc_worker [xfs] [ 4277.393551] RIP: 0010:__list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.394518] Code: 48 91 82 e8 37 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 28 49 91 82 e8 26 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 58 49 91 [ 4277.397292] RSP: 0018:ffffc90000333b38 EFLAGS: 00010082 [ 4277.398202] RAX: 000000000000004e RBX: ffffea00044b3e50 RCX: 0000000000000000 [ 4277.399340] RDX: 0000000000000002 RSI: ffffffff828f8715 RDI: 00000000ffffffff [ 4277.400545] RBP: ffffea00044b3e40 R08: 0000000000000000 R09: ffffc900003339f0 [ 4277.401710] R10: 0000000000000003 R11: ffffffff82d44088 R12: ffff888112cf9910 [ 4277.402887] R13: 0000000000000001 R14: 0000000000000001 R15: ffff8881000424c0 [ 4277.404049] FS: 0000000000000000(0000) GS:ffff88842fd40000(0000) knlGS:0000000000000000 [ 4277.405357] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4277.406389] CR2: 00007f2ad0b24000 CR3: 0000000102a3a006 CR4: 00000000007706e0 [ 4277.407589] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4277.408780] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4277.410000] PKRU: 55555554 [ 4277.410645] Call Trace: [ 4277.411234] <TASK> [ 4277.411777] ? die+0x32/0x80 [ 4277.412439] ? do_trap+0xd6/0x100 [ 4277.413150] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.414158] ? do_error_trap+0x6a/0x90 [ 4277.414948] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.415915] ? exc_invalid_op+0x4c/0x60 [ 4277.416710] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.417675] ? asm_exc_invalid_op+0x16/0x20 [ 4277.418482] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.419466] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.420410] free_to_partial_list+0x515/0x5e0 [ 4277.421242] ? xfs_iext_remove+0x41a/0xa10 [xfs] [ 4277.422298] xfs_iext_remove+0x41a/0xa10 [xfs] [ 4277.423316] ? xfs_inodegc_worker+0xb4/0x1a0 [xfs] [ 4277.424383] xfs_bmap_del_extent_delay+0x4fe/0x7d0 [xfs] [ 4277.425490] __xfs_bunmapi+0x50d/0x840 [xfs] [ 4277.426445] xfs_itruncate_extents_flags+0x13a/0x490 [xfs] [ 4277.427553] xfs_inactive_truncate+0xa3/0x120 [xfs] [ 4277.428567] xfs_inactive+0x22d/0x290 [xfs] [ 4277.429500] xfs_inodegc_worker+0xb4/0x1a0 [xfs] [ 4277.430479] process_one_work+0x171/0x340 [ 4277.431227] worker_thread+0x277/0x390 [ 4277.431962] ? __pfx_worker_thread+0x10/0x10 [ 4277.432752] kthread+0xf0/0x120 [ 4277.433382] ? __pfx_kthread+0x10/0x10 [ 4277.434134] ret_from_fork+0x2d/0x50 [ 4277.434837] ? __pfx_kthread+0x10/0x10 [ 4277.435566] ret_from_fork_asm+0x1b/0x30 [ 4277.436280] </TASK>
CVE-2024-53178 1 Linux 1 Linux Kernel 2026-10-30 7.5 High
In the Linux kernel, the following vulnerability has been resolved: smb: Don't leak cfid when reconnect races with open_cached_dir open_cached_dir() may either race with the tcon reconnection even before compound_send_recv() or directly trigger a reconnection via SMB2_open_init() or SMB_query_info_init(). The reconnection process invokes invalidate_all_cached_dirs() via cifs_mark_open_files_invalid(), which removes all cfids from the cfids->entries list but doesn't drop a ref if has_lease isn't true. This results in the currently-being-constructed cfid not being on the list, but still having a refcount of 2. It leaks if returned from open_cached_dir(). Fix this by setting cfid->has_lease when the ref is actually taken; the cfid will not be used by other threads until it has a valid time. Addresses these kmemleaks: unreferenced object 0xffff8881090c4000 (size 1024): comm "bash", pid 1860, jiffies 4295126592 hex dump (first 32 bytes): 00 01 00 00 00 00 ad de 22 01 00 00 00 00 ad de ........"....... 00 ca 45 22 81 88 ff ff f8 dc 4f 04 81 88 ff ff ..E"......O..... backtrace (crc 6f58c20f): [<ffffffff8b895a1e>] __kmalloc_cache_noprof+0x2be/0x350 [<ffffffff8bda06e3>] open_cached_dir+0x993/0x1fb0 [<ffffffff8bdaa750>] cifs_readdir+0x15a0/0x1d50 [<ffffffff8b9a853f>] iterate_dir+0x28f/0x4b0 [<ffffffff8b9a9aed>] __x64_sys_getdents64+0xfd/0x200 [<ffffffff8cf6da05>] do_syscall_64+0x95/0x1a0 [<ffffffff8d00012f>] entry_SYSCALL_64_after_hwframe+0x76/0x7e unreferenced object 0xffff8881044fdcf8 (size 8): comm "bash", pid 1860, jiffies 4295126592 hex dump (first 8 bytes): 00 cc cc cc cc cc cc cc ........ backtrace (crc 10c106a9): [<ffffffff8b89a3d3>] __kmalloc_node_track_caller_noprof+0x363/0x480 [<ffffffff8b7d7256>] kstrdup+0x36/0x60 [<ffffffff8bda0700>] open_cached_dir+0x9b0/0x1fb0 [<ffffffff8bdaa750>] cifs_readdir+0x15a0/0x1d50 [<ffffffff8b9a853f>] iterate_dir+0x28f/0x4b0 [<ffffffff8b9a9aed>] __x64_sys_getdents64+0xfd/0x200 [<ffffffff8cf6da05>] do_syscall_64+0x95/0x1a0 [<ffffffff8d00012f>] entry_SYSCALL_64_after_hwframe+0x76/0x7e And addresses these BUG splats when unmounting the SMB filesystem: BUG: Dentry ffff888140590ba0{i=1000000000080,n=/} still in use (2) [unmount of cifs cifs] WARNING: CPU: 3 PID: 3433 at fs/dcache.c:1536 umount_check+0xd0/0x100 Modules linked in: CPU: 3 UID: 0 PID: 3433 Comm: bash Not tainted 6.12.0-rc4-g850925a8133c-dirty #49 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 RIP: 0010:umount_check+0xd0/0x100 Code: 8d 7c 24 40 e8 31 5a f4 ff 49 8b 54 24 40 41 56 49 89 e9 45 89 e8 48 89 d9 41 57 48 89 de 48 c7 c7 80 e7 db ac e8 f0 72 9a ff <0f> 0b 58 31 c0 5a 5b 5d 41 5c 41 5d 41 5e 41 5f e9 2b e5 5d 01 41 RSP: 0018:ffff88811cc27978 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff888140590ba0 RCX: ffffffffaaf20bae RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff8881f6fb6f40 RBP: ffff8881462ec000 R08: 0000000000000001 R09: ffffed1023984ee3 R10: ffff88811cc2771f R11: 00000000016cfcc0 R12: ffff888134383e08 R13: 0000000000000002 R14: ffff8881462ec668 R15: ffffffffaceab4c0 FS: 00007f23bfa98740(0000) GS:ffff8881f6f80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556de4a6f808 CR3: 0000000123c80000 CR4: 0000000000350ef0 Call Trace: <TASK> d_walk+0x6a/0x530 shrink_dcache_for_umount+0x6a/0x200 generic_shutdown_super+0x52/0x2a0 kill_anon_super+0x22/0x40 cifs_kill_sb+0x159/0x1e0 deactivate_locked_super+0x66/0xe0 cleanup_mnt+0x140/0x210 task_work_run+0xfb/0x170 syscall_exit_to_user_mode+0x29f/0x2b0 do_syscall_64+0xa1/0x1a0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f23bfb93ae7 Code: ff ff ff ff c3 66 0f 1f 44 00 00 48 8b 0d 11 93 0d 00 f7 d8 64 89 01 b8 ff ff ff ff eb bf 0f 1f 44 00 00 b8 50 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e9 92 0d 00 f7 d8 64 89 ---truncated---
CVE-2024-43913 1 Linux 1 Linux Kernel 2026-10-30 7 High
In the Linux kernel, the following vulnerability has been resolved: nvme: apple: fix device reference counting Drivers must call nvme_uninit_ctrl after a successful nvme_init_ctrl. Split the allocation side out to make the error handling boundary easier to navigate. The apple driver had been doing this wrong, leaking the controller device memory on a tagset failure.
CVE-2024-41023 2 Linux, Redhat 3 Linux Kernel, Enterprise Linux, Rhel Eus 2026-10-30 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: sched/deadline: Fix task_struct reference leak During the execution of the following stress test with linux-rt: stress-ng --cyclic 30 --timeout 30 --minimize --quiet kmemleak frequently reported a memory leak concerning the task_struct: unreferenced object 0xffff8881305b8000 (size 16136): comm "stress-ng", pid 614, jiffies 4294883961 (age 286.412s) object hex dump (first 32 bytes): 02 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 .@.............. 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ debug hex dump (first 16 bytes): 53 09 00 00 00 00 00 00 00 00 00 00 00 00 00 00 S............... backtrace: [<00000000046b6790>] dup_task_struct+0x30/0x540 [<00000000c5ca0f0b>] copy_process+0x3d9/0x50e0 [<00000000ced59777>] kernel_clone+0xb0/0x770 [<00000000a50befdc>] __do_sys_clone+0xb6/0xf0 [<000000001dbf2008>] do_syscall_64+0x5d/0xf0 [<00000000552900ff>] entry_SYSCALL_64_after_hwframe+0x6e/0x76 The issue occurs in start_dl_timer(), which increments the task_struct reference count and sets a timer. The timer callback, dl_task_timer, is supposed to decrement the reference count upon expiration. However, if enqueue_task_dl() is called before the timer expires and cancels it, the reference count is not decremented, leading to the leak. This patch fixes the reference leak by ensuring the task_struct reference count is properly decremented when the timer is canceled.
CVE-2024-36911 1 Linux 1 Linux Kernel 2026-10-30 9.8 Critical
In the Linux kernel, the following vulnerability has been resolved: hv_netvsc: Don't free decrypted memory In CoCo VMs it is possible for the untrusted host to cause set_memory_encrypted() or set_memory_decrypted() to fail such that an error is returned and the resulting memory is shared. Callers need to take care to handle these errors to avoid returning decrypted (shared) memory to the page allocator, which could lead to functional or security issues. The netvsc driver could free decrypted/shared pages if set_memory_decrypted() fails. Check the decrypted field in the gpadl to decide whether to free the memory.
CVE-2024-27011 2 Linux, Redhat 3 Linux Kernel, Enterprise Linux, Rhel Eus 2026-10-30 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: fix memleak in map from abort path The delete set command does not rely on the transaction object for element removal, therefore, a combination of delete element + delete set from the abort path could result in restoring twice the refcount of the mapping. Check for inactive element in the next generation for the delete element command in the abort path, skip restoring state if next generation bit has been already cleared. This is similar to the activate logic using the set walk iterator. [ 6170.286929] ------------[ cut here ]------------ [ 6170.286939] WARNING: CPU: 6 PID: 790302 at net/netfilter/nf_tables_api.c:2086 nf_tables_chain_destroy+0x1f7/0x220 [nf_tables] [ 6170.287071] Modules linked in: [...] [ 6170.287633] CPU: 6 PID: 790302 Comm: kworker/6:2 Not tainted 6.9.0-rc3+ #365 [ 6170.287768] RIP: 0010:nf_tables_chain_destroy+0x1f7/0x220 [nf_tables] [ 6170.287886] Code: df 48 8d 7d 58 e8 69 2e 3b df 48 8b 7d 58 e8 80 1b 37 df 48 8d 7d 68 e8 57 2e 3b df 48 8b 7d 68 e8 6e 1b 37 df 48 89 ef eb c4 <0f> 0b 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 0f [ 6170.287895] RSP: 0018:ffff888134b8fd08 EFLAGS: 00010202 [ 6170.287904] RAX: 0000000000000001 RBX: ffff888125bffb28 RCX: dffffc0000000000 [ 6170.287912] RDX: 0000000000000003 RSI: ffffffffa20298ab RDI: ffff88811ebe4750 [ 6170.287919] RBP: ffff88811ebe4700 R08: ffff88838e812650 R09: fffffbfff0623a55 [ 6170.287926] R10: ffffffff8311d2af R11: 0000000000000001 R12: ffff888125bffb10 [ 6170.287933] R13: ffff888125bffb10 R14: dead000000000122 R15: dead000000000100 [ 6170.287940] FS: 0000000000000000(0000) GS:ffff888390b00000(0000) knlGS:0000000000000000 [ 6170.287948] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6170.287955] CR2: 00007fd31fc00710 CR3: 0000000133f60004 CR4: 00000000001706f0 [ 6170.287962] Call Trace: [ 6170.287967] <TASK> [ 6170.287973] ? __warn+0x9f/0x1a0 [ 6170.287986] ? nf_tables_chain_destroy+0x1f7/0x220 [nf_tables] [ 6170.288092] ? report_bug+0x1b1/0x1e0 [ 6170.287986] ? nf_tables_chain_destroy+0x1f7/0x220 [nf_tables] [ 6170.288092] ? report_bug+0x1b1/0x1e0 [ 6170.288104] ? handle_bug+0x3c/0x70 [ 6170.288112] ? exc_invalid_op+0x17/0x40 [ 6170.288120] ? asm_exc_invalid_op+0x1a/0x20 [ 6170.288132] ? nf_tables_chain_destroy+0x2b/0x220 [nf_tables] [ 6170.288243] ? nf_tables_chain_destroy+0x1f7/0x220 [nf_tables] [ 6170.288366] ? nf_tables_chain_destroy+0x2b/0x220 [nf_tables] [ 6170.288483] nf_tables_trans_destroy_work+0x588/0x590 [nf_tables]
CVE-2023-53261 1 Linux 1 Linux Kernel 2026-10-30 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: coresight: Fix memory leak in acpi_buffer->pointer There are memory leaks reported by kmemleak: ... unreferenced object 0xffff00213c141000 (size 1024): comm "systemd-udevd", pid 2123, jiffies 4294909467 (age 6062.160s) hex dump (first 32 bytes): 04 00 00 00 02 00 00 00 18 10 14 3c 21 00 ff ff ...........<!... 00 00 00 00 00 00 00 00 03 00 00 00 10 00 00 00 ................ backtrace: [<000000004b7c9001>] __kmem_cache_alloc_node+0x2f8/0x348 [<00000000b0fc7ceb>] __kmalloc+0x58/0x108 [<0000000064ff4695>] acpi_os_allocate+0x2c/0x68 [<000000007d57d116>] acpi_ut_initialize_buffer+0x54/0xe0 [<0000000024583908>] acpi_evaluate_object+0x388/0x438 [<0000000017b2e72b>] acpi_evaluate_object_typed+0xe8/0x240 [<000000005df0eac2>] coresight_get_platform_data+0x1b4/0x988 [coresight] ... The ACPI buffer memory (buf.pointer) should be freed. But the buffer is also used after returning from acpi_get_dsd_graph(). Move the temporary variables buf to acpi_coresight_parse_graph(), and free it before the function return to prevent memory leak.
CVE-2023-52653 2 Linux, Redhat 3 Linux Kernel, Enterprise Linux, Rhel Eus 2026-10-30 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: SUNRPC: fix a memleak in gss_import_v2_context The ctx->mech_used.data allocated by kmemdup is not freed in neither gss_import_v2_context nor it only caller gss_krb5_import_sec_context, which frees ctx on error. Thus, this patch reform the last call of gss_import_v2_context to the gss_krb5_import_ctx_v2, preventing the memleak while keepping the return formation.
CVE-2026-83677 1 Microsoft 10 Windows 11 24h2, Windows 11 24h2, Windows 11 25h2 and 7 more 2026-10-29 7.5 High
Missing release of memory after effective lifetime in Windows DHCP Client allows an unauthorized attacker to deny service over a network.
CVE-2026-110685 1 Rurban 1 Cpanel::json::xs 2026-10-29 9.1 Critical
Cpanel::JSON::XS versions before 4.80 for Perl leak the decoded arguments of a tagged value when its THAW method dies in decode_tag. With allow_tags, a tagged value's class name and argument array are decoded and passed to the class's THAW method. Both are released only after THAW returns, so a THAW that dies leaves the whole decoded argument structure allocated. Each rejected document leaks data of a size the sender chooses, so a process that catches the error and keeps running exhausts its memory.
CVE-2026-110684 1 Rurban 1 Cpanel::json::xs 2026-10-29 8.1 High
Cpanel::JSON::XS versions from 3.0202 before 4.80 for Perl leak memory and retain overloaded objects when encoding values as strings in encode_stringify. encode_stringify writes a value in its string form under allow_stringify, under convert_blessed for objects without TO_JSON, and under allow_bignum. For an array or hash object with a "" overload, and from 4.20 a scalar object, it takes an extra reference that is never released, so the object and everything it references are never freed. From 4.10 it also never frees its copy of the string. Repeatedly encoding data that contains such values grows process memory without bound.
CVE-2026-110677 1 Rurban 1 Cpanel::json::xs 2026-10-29 7.5 High
Cpanel::JSON::XS versions from 4.28 before 4.80 for Perl leak the array collecting duplicate key values under dupkeys_as_arrayref in decode_hv. With dupkeys_as_arrayref, the values of a duplicate object key are collected into a new array. An extra reference is never released, so the array and every value in it outlive the decoded structure. The array also leaks when decoding fails after a duplicate key. Repeatedly decoding untrusted JSON with a duplicate key holding a large value exhausts process memory.
CVE-2026-110672 1 Rurban 1 Cpanel::json::xs 2026-10-29 7.5 High
Cpanel::JSON::XS versions before 4.80 for Perl leak the decoded key of an object rejected for a duplicate key or a missing colon in decode_hv. A quoted key of 24 or more bytes, or one containing a non-ASCII byte or an escape sequence, is decoded into a new scalar. Nothing frees that scalar when the object is rejected for a missing ':' after the key or, from 4.09, for a duplicate key. Duplicate keys are an error unless allow_dupkeys, dupkeys_as_arrayref or relaxed is set. A process that keeps running after a failed decode retains one key per rejected document, with its size chosen by the sender. Repeated requests exhaust process memory.
CVE-2026-116158 1 Imagemagick 1 Imagemagick 2026-10-26 2.5 Low
ImageMagick before 7.1.2-33 contains a memory leak vulnerability in the magick compare command caused by missing cleanup when an operation fails. Attackers can supply inputs that trigger repeated failed compare operations to exhaust memory and cause denial of service.
CVE-2026-116157 1 Imagemagick 1 Imagemagick 2026-10-26 3.3 Low
ImageMagick before 7.1.2-33 contains a memory leak vulnerability in PerlMagick that fails to free values returned when reading image properties. Attackers can repeatedly trigger property reads through five affected PerlMagick code locations to exhaust memory and cause denial of service.
CVE-2026-116156 1 Imagemagick 1 Imagemagick 2026-10-26 3.3 Low
ImageMagick before 6.9.13-58 and 7.x before 7.1.2-33 contains a memory leak caused by a missing cleanup when the -set profile option is used. An attacker who induces a user to process images with the -set profile option can leak memory, potentially exhausting resources and causing a denial of service.
CVE-2026-116154 1 Imagemagick 1 Imagemagick 2026-10-26 5.3 Medium
ImageMagick before 6.9.13-58 and 7.x before 7.1.2-33 contains a memory leak in its XML parsing code, where allocated memory is not released when parsing reaches the nesting depth limit. Attackers can supply crafted, deeply nested XML data to trigger the leak, causing memory exhaustion and denial of service.