In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive. Not checking the active flag during refresh is particularly egregious, as KVM can end up with a valid, inactive cache, which can lead to a variety of use-after-free bugs, e.g. consuming a NULL kernel pointer or missing an mmu_notifier invalidation due to the cache not being on the list of gfns to invalidate. Note, "active" needs to be set if and only if the cache is on the list of caches, i.e. is reachable via mmu_notifier events. If a relevant mmu_notifier event occurs while the cache is "active" but not on the list, KVM will not acquire the cache's lock and so will not serailize the mmu_notifier event with active users and/or kvm_gpc_refresh(). A race between KVM_XEN_ATTR_TYPE_SHARED_INFO and KVM_XEN_HVM_EVTCHN_SEND can be exploited to trigger the bug. 1. Deactivate shinfo cache: kvm_xen_hvm_set_attr case KVM_XEN_ATTR_TYPE_SHARED_INFO kvm_gpc_deactivate kvm_gpc_unmap gpc->valid = false gpc->khva = NULL gpc->active = false Result: active = false, valid = false 2. Cause cache refresh: kvm_arch_vm_ioctl case KVM_XEN_HVM_EVTCHN_SEND kvm_xen_hvm_evtchn_send kvm_xen_set_evtchn kvm_xen_set_evtchn_fast kvm_gpc_check return -EWOULDBLOCK because !gpc->valid kvm_xen_set_evtchn_fast return -EWOULDBLOCK kvm_gpc_refresh hva_to_pfn_retry gpc->valid = true gpc->khva = not NULL Result: active = false, valid = true 3. Race ioctl KVM_XEN_HVM_EVTCHN_SEND against ioctl KVM_XEN_ATTR_TYPE_SHARED_INFO: kvm_arch_vm_ioctl case KVM_XEN_HVM_EVTCHN_SEND kvm_xen_hvm_evtchn_send kvm_xen_set_evtchn kvm_xen_set_evtchn_fast read_lock gpc->lock kvm_xen_hvm_set_attr case KVM_XEN_ATTR_TYPE_SHARED_INFO mutex_lock kvm->lock kvm_xen_shared_info_init kvm_gpc_activate gpc->khva = NULL kvm_gpc_check [ Check passes because gpc->valid is still true, even though gpc->khva is already NULL. ] shinfo = gpc->khva pending_bits = shinfo->evtchn_pending CRASH: test_and_set_bit(..., pending_bits)

The AlmaLinux 9.2 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare ALMALINUX9.2:CLSA-2025:1765463110 advisory.

  - In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or     refresh inactive gfn_to_pfn_cache Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive.
    Not checking the active flag during refresh is particularly egregious, as KVM can end up with a valid,     inactive cache, which can lead to a variety of use-after-free bugs, e.g. consuming a NULL kernel pointer     or missing an mmu_notifier invalidation due to the cache not being on the list of gfns to invalidate.
    Note, active needs to be set if and only if the cache is on the list of caches, i.e. is reachable via     mmu_notifier events. If a relevant mmu_notifier event occurs while the cache is active but not on the     list, KVM will not acquire the cache's lock and so will not serailize the mmu_notifier event with active     users and/or kvm_gpc_refresh(). A race between KVM_XEN_ATTR_TYPE_SHARED_INFO and KVM_XEN_HVM_EVTCHN_SEND     can be exploited to trigger the bug. 1. Deactivate shinfo cache: kvm_xen_hvm_set_attr case     KVM_XEN_ATTR_TYPE_SHARED_INFO kvm_gpc_deactivate kvm_gpc_unmap gpc->valid = false gpc->khva = NULL     gpc->active = false Result: active = false, valid = false 2. Cause cache refresh: kvm_arch_vm_ioctl case     KVM_XEN_HVM_EVTCHN_SEND kvm_xen_hvm_evtchn_send kvm_xen_set_evtchn kvm_xen_set_evtchn_fast kvm_gpc_check     return -EWOULDBLOCK because !gpc->valid kvm_xen_set_evtchn_fast return -EWOULDBLOCK kvm_gpc_refresh     hva_to_pfn_retry gpc->valid = true gpc->khva = not NULL Result: active = false, valid = true 3. Race ioctl     KVM_XEN_HVM_EVTCHN_SEND against ioctl KVM_XEN_ATTR_TYPE_SHARED_INFO: kvm_arch_vm_ioctl case     KVM_XEN_HVM_EVTCHN_SEND kvm_xen_hvm_evtchn_send kvm_xen_set_evtchn kvm_xen_set_evtchn_fast read_lock     gpc->lock kvm_xen_hvm_set_attr case KVM_XEN_ATTR_TYPE_SHARED_INFO mutex_lock kvm->lock     kvm_xen_shared_info_init kvm_gpc_activate gpc->khva = NULL kvm_gpc_check [ Check passes because gpc->valid     is still true, even though gpc->khva is already NULL. ] shinfo = gpc->khva pending_bits =     shinfo->evtchn_pending CRASH: test_and_set_bit(..., pending_bits) (CVE-2022-49882)

  - In the Linux kernel, the following vulnerability has been resolved: coresight: Clear the connection field     properly coresight devices track their connections (output connections) and hold a reference to the     fwnode. When a device goes away, we walk through the devices on the coresight bus and make sure that the     references are dropped. This happens both ways: a) For all output connections from the device, drop the     reference to the target device via coresight_release_platform_data() b) Iterate over all the devices on     the coresight bus and drop the reference to fwnode if *this* device is the target of the output     connection, via coresight_remove_conns()->coresight_remove_match(). However, the coresight_remove_match()     doesn't clear the fwnode field, after dropping the reference, this causes use-after-free and additional     refcount drops on the fwnode. e.g., if we have two devices, A and B, with a connection, A -> B. If we     remove B first, B would clear the reference on B, from A via coresight_remove_match(). But when A is     removed, it still has a connection with fwnode still pointing to B. Thus it tries to drops the reference     in coresight_release_platform_data(), raising the bells like : [ 91.990153] ------------[ cut here     ]------------ [ 91.990163] refcount_t: addition on 0; use-after-free. [ 91.990212] WARNING: CPU: 0 PID:
    461 at lib/refcount.c:25 refcount_warn_saturate+0xa0/0x144 [ 91.990260] Modules linked in:
    coresight_funnel coresight_replicator coresight_etm4x(-) crct10dif_ce coresight ip_tables x_tables ipv6     [last unloaded: coresight_cpu_debug] [ 91.990398] CPU: 0 PID: 461 Comm: rmmod Tainted: G W T 5.19.0-rc2+     #53 [ 91.990418] Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS     EDK II Feb 1 2019 [ 91.990434] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [     91.990454] pc : refcount_warn_saturate+0xa0/0x144 [ 91.990476] lr : refcount_warn_saturate+0xa0/0x144 [     91.990496] sp : ffff80000c843640 [ 91.990509] x29: ffff80000c843640 x28: ffff800009957c28 x27:
    ffff80000c8439a8 [ 91.990560] x26: ffff00097eff1990 x25: ffff8000092b6ad8 x24: ffff00097eff19a8 [     91.990610] x23: ffff80000c8439a8 x22: 0000000000000000 x21: ffff80000c8439c2 [ 91.990659] x20:
    0000000000000000 x19: ffff00097eff1a10 x18: ffff80000ab99c40 [ 91.990708] x17: 0000000000000000 x16:
    0000000000000000 x15: ffff80000abf6fa0 [ 91.990756] x14: 000000000000001d x13: 0a2e656572662d72 x12:
    657466612d657375 [ 91.990805] x11: 203b30206e6f206e x10: 6f69746964646120 x9 : ffff8000081aba28 [     91.990854] x8 : 206e6f206e6f6974 x7 : 69646461203a745f x6 : 746e756f63666572 [ 91.990903] x5 :
    ffff00097648ec58 x4 : 0000000000000000 x3 : 0000000000000027 [ 91.990952] x2 : 0000000000000000 x1 :
    0000000000000000 x0 : ffff00080260ba00 [ 91.991000] Call trace: [ 91.991012]     refcount_warn_saturate+0xa0/0x144 [ 91.991034] kobject_get+0xac/0xb0 [ 91.991055] of_node_get+0x2c/0x40 [     91.991076] of_fwnode_get+0x40/0x60 [ 91.991094] fwnode_handle_get+0x3c/0x60 [ 91.991116]     fwnode_get_nth_parent+0xf4/0x110 [ 91.991137] fwnode_full_name_string+0x48/0xc0 [ 91.991158]     device_node_string+0x41c/0x530 [ 91.991178] pointer+0x320/0x3ec [ 91.991198] vsnprintf+0x23c/0x750 [     91.991217] vprintk_store+0x104/0x4b0 [ 91.991238] vprintk_emit+0x8c/0x360 [ 91.991257]     vprintk_default+0x44/0x50 [ 91.991276] vprintk+0xcc/0xf0 [ 91.991295] _printk+0x68/0x90 [ 91.991315]     of_node_release+0x13c/0x14c [ 91.991334] kobject_put+0x98/0x114 [ 91.991354] of_node_put+0x24/0x34 [     91.991372] of_fwnode_put+0x40/0x5c [ 91.991390] fwnode_handle_put+0x38/0x50 [ 91.991411]     coresight_release_platform_data+0x74/0xb0 [coresight] [ 91.991472] coresight_unregister+0x64/0xcc     [coresight] [ 91.991525] etm4_remove_dev+0x64/0x78 [coresight_etm4x] [ 91.991563]     etm4_remove_amba+0x1c/0x2c [coresight_etm4x] [ 91.991598] amba_remove+0x3c/0x19c ---truncated---     (CVE-2022-50214)

  - In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix potential stack-     out-of-bounds in brcmf_c_preinit_dcmds() This patch fixes a stack-out-of-bounds read in brcmfmac that     occurs when 'buf' that is not null-terminated is passed as an argument of strsep() in     brcmf_c_preinit_dcmds(). This buffer is filled with a firmware version string by memcpy() in     brcmf_fil_iovar_data_get(). The patch ensures buf is null-terminated. Found by a modified version of     syzkaller. [ 47.569679][ T1897] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43236b for chip     BCM43236/3 [ 47.582839][ T1897] brcmfmac: brcmf_c_process_clm_blob: no clm_blob available (err=-2), device     may have limited channels available [ 47.601565][ T1897]     ================================================================== [ 47.602574][ T1897] BUG: KASAN: stack-     out-of-bounds in strsep+0x1b2/0x1f0 [ 47.603447][ T1897] Read of size 1 at addr ffffc90001f6f000 by task     kworker/0:2/1897 [ 47.604336][ T1897] [ 47.604621][ T1897] CPU: 0 PID: 1897 Comm: kworker/0:2 Tainted: G O     5.14.0+ #131 [ 47.605617][ T1897] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS     rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 [ 47.606907][ T1897] Workqueue: usb_hub_wq     hub_event [ 47.607453][ T1897] Call Trace: [ 47.607801][ T1897] dump_stack_lvl+0x8e/0xd1 [ 47.608295][     T1897] print_address_description.constprop.0.cold+0xf/0x334 [ 47.609009][ T1897] ? strsep+0x1b2/0x1f0 [     47.609434][ T1897] ? strsep+0x1b2/0x1f0 [ 47.609863][ T1897] kasan_report.cold+0x83/0xdf [ 47.610366][     T1897] ? strsep+0x1b2/0x1f0 [ 47.610882][ T1897] strsep+0x1b2/0x1f0 [ 47.611300][ T1897] ?     brcmf_fil_iovar_data_get+0x3a/0xf0 [ 47.611883][ T1897] brcmf_c_preinit_dcmds+0x995/0xc40 [ 47.612434][     T1897] ? brcmf_c_set_joinpref_default+0x100/0x100 [ 47.613078][ T1897] ?     rcu_read_lock_sched_held+0xa1/0xd0 [ 47.613662][ T1897] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 47.614208][     T1897] ? lock_acquire+0x19d/0x4e0 [ 47.614704][ T1897] ? find_held_lock+0x2d/0x110 [ 47.615236][ T1897] ?     brcmf_usb_deq+0x1a7/0x260 [ 47.615741][ T1897] ? brcmf_usb_rx_fill_all+0x5a/0xf0 [ 47.616288][ T1897]     brcmf_attach+0x246/0xd40 [ 47.616758][ T1897] ? wiphy_new_nm+0x1703/0x1dd0 [ 47.617280][ T1897] ?     kmemdup+0x43/0x50 [ 47.617720][ T1897] brcmf_usb_probe+0x12de/0x1690 [ 47.618244][ T1897] ?     brcmf_usbdev_qinit.constprop.0+0x470/0x470 [ 47.618901][ T1897] usb_probe_interface+0x2aa/0x760 [     47.619429][ T1897] ? usb_probe_device+0x250/0x250 [ 47.619950][ T1897] really_probe+0x205/0xb70 [     47.620435][ T1897] ? driver_allows_async_probing+0x130/0x130 [ 47.621048][ T1897]
    __driver_probe_device+0x311/0x4b0 [ 47.621595][ T1897] ? driver_allows_async_probing+0x130/0x130 [     47.622209][ T1897] driver_probe_device+0x4e/0x150 [ 47.622739][ T1897] __device_attach_driver+0x1cc/0x2a0     [ 47.623287][ T1897] bus_for_each_drv+0x156/0x1d0 [ 47.623796][ T1897] ? bus_rescan_devices+0x30/0x30 [     47.624309][ T1897] ? lockdep_hardirqs_on_prepare+0x273/0x3e0 [ 47.624907][ T1897] ?     trace_hardirqs_on+0x46/0x160 [ 47.625437][ T1897] __device_attach+0x23f/0x3a0 [ 47.625924][ T1897] ?     device_bind_driver+0xd0/0xd0 [ 47.626433][ T1897] ? kobject_uevent_env+0x287/0x14b0 [ 47.627057][ T1897]     bus_probe_device+0x1da/0x290 [ 47.627557][ T1897] device_add+0xb7b/0x1eb0 [ 47.628027][ T1897] ?     wait_for_completion+0x290/0x290 [ 47.628593][ T1897] ? __fw_devlink_link_to_suppliers+0x5a0/0x5a0 [     47.629249][ T1897] usb_set_configuration+0xf59/0x16f0 [ 47.629829][ T1897]     usb_generic_driver_probe+0x82/0xa0 [ 47.630385][ T1897] usb_probe_device+0xbb/0x250 [ 47.630927][ T1897] ?     usb_suspend+0x590/0x590 [ 47.631397][ T1897] really_probe+0x205/0xb70 [ 47.631855][ T1897] ?     driver_allows_async_probing+0x130/0x130 [ 47.632469][ T1897] __driver_probe_device+0x311/0x4b0 [     47.633002][ ---truncated--- (CVE-2022-50258)

  - In the Linux kernel, the following vulnerability has been resolved: netlink: prevent potential spectre v1     gadgets Most netlink attributes are parsed and validated from __nla_validate_parse() or validate_nla() u16     type = nla_type(nla); if (type == 0 || type > maxtype) { /* error or continue */ } @type is then used as     an array index and can be used as a Spectre v1 gadget. array_index_nospec() can be used to prevent leaking     content of kernel memory to malicious users. This should take care of vast majority of netlink uses, but     an audit is needed to take care of others where validation is not yet centralized in core netlink     functions. (CVE-2023-53000)

  - In the Linux kernel, the following vulnerability has been resolved: scsi: mpi3mr: Bad drive in topology     results kernel crash When the SAS Transport Layer support is enabled and a device exposed to the OS by the     driver fails INQUIRY commands, the driver frees up the memory allocated for an internal HBA port data     structure. However, in some places, the reference to the freed memory is not cleared. When the firmware     sends the Device Info change event for the same device again, the freed memory is accessed and that leads     to memory corruption and OS crash. (CVE-2023-53037)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - In the Linux kernel, the following vulnerability has been resolved: KVM: Reject attempts to consume or     refresh inactive gfn_to_pfn_cache Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive.
    Not checking the active flag during refresh is particularly egregious, as KVM can end up with a valid,     inactive cache, which can lead to a variety of use-after-free bugs, e.g. consuming a NULL kernel pointer     or missing an mmu_notifier invalidation due to the cache not being on the list of gfns to invalidate.
    Note, active needs to be set if and only if the cache is on the list of caches, i.e. is reachable via     mmu_notifier events. If a relevant mmu_notifier event occurs while the cache is active but not on the     list, KVM will not acquire the cache's lock and so will not serailize the mmu_notifier event with active     users and/or kvm_gpc_refresh(). A race between KVM_XEN_ATTR_TYPE_SHARED_INFO and KVM_XEN_HVM_EVTCHN_SEND     can be exploited to trigger the bug. 1. Deactivate shinfo cache: kvm_xen_hvm_set_attr case     KVM_XEN_ATTR_TYPE_SHARED_INFO kvm_gpc_deactivate kvm_gpc_unmap gpc->valid = false gpc->khva = NULL     gpc->active = false Result: active = false, valid = false 2. Cause cache refresh: kvm_arch_vm_ioctl case     KVM_XEN_HVM_EVTCHN_SEND kvm_xen_hvm_evtchn_send kvm_xen_set_evtchn kvm_xen_set_evtchn_fast kvm_gpc_check     return -EWOULDBLOCK because !gpc->valid kvm_xen_set_evtchn_fast return -EWOULDBLOCK kvm_gpc_refresh     hva_to_pfn_retry gpc->valid = true gpc->khva = not NULL Result: active = false, valid = true 3. Race ioctl     KVM_XEN_HVM_EVTCHN_SEND against ioctl KVM_XEN_ATTR_TYPE_SHARED_INFO: kvm_arch_vm_ioctl case     KVM_XEN_HVM_EVTCHN_SEND kvm_xen_hvm_evtchn_send kvm_xen_set_evtchn kvm_xen_set_evtchn_fast read_lock     gpc->lock kvm_xen_hvm_set_attr case KVM_XEN_ATTR_TYPE_SHARED_INFO mutex_lock kvm->lock     kvm_xen_shared_info_init kvm_gpc_activate gpc->khva = NULL kvm_gpc_check [ Check passes because gpc->valid     is still true, even though gpc->khva is already NULL. ] shinfo = gpc->khva pending_bits =     shinfo->evtchn_pending CRASH: test_and_set_bit(..., pending_bits) (CVE-2022-49882)

Note that Nessus relies on the presence of the package as reported by the vendor.

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2023:6583 advisory.

    The kernel packages contain the Linux kernel, the core of any Linux operating system.

    Security Fix(es):

    * kernel: net/sched: cls_u32 component reference counter leak if tcf_change_indev() fails (CVE-2023-3609)

    * kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and     cls_route (CVE-2023-4128, CVE-2023-4206, CVE-2023-4207, CVE-2023-4208)

    * kernel: eBPF: insufficient stack type checks in dynptr (CVE-2023-39191)

    * Kernel: race when faulting a device private page in memory manager (CVE-2022-3523)

    * kernel: use-after-free in l1oip timer handlers (CVE-2022-3565)

    * kernel: Rate limit overflow messages in r8152 in intr_callback (CVE-2022-3594)

    * kernel: vmwgfx: use-after-free in vmw_cmd_res_check (CVE-2022-38457)

    * kernel: vmwgfx: use-after-free in vmw_execbuf_tie_context (CVE-2022-40133)

    * hw: Intel: Gather Data Sampling (GDS) side channel vulnerability (CVE-2022-40982)

    * kernel: Information leak in l2cap_parse_conf_req in net/bluetooth/l2cap_core.c (CVE-2022-42895)

    * kernel: x86/mm: Randomize per-cpu entry area (CVE-2023-0597)

    * kernel: HID: check empty report_list in hid_validate_values() (CVE-2023-1073)

    * kernel: sctp: fail if no bound addresses can be used for a given scope (CVE-2023-1074)

    * kernel: hid: Use After Free in asus_remove() (CVE-2023-1079)

    * kernel: hash collisions in the IPv6 connection lookup table (CVE-2023-1206)

    * kernel: ovl: fix use after free in struct ovl_aio_req (CVE-2023-1252)

    * Kernel: use-after-free in nfsd4_ssc_setup_dul in fs/nfsd/nfs4proc.c (CVE-2023-1652)

    * kernel: Use after free bug in btsdio_remove due to race condition (CVE-2023-1989)

    * kernel: fbcon: shift-out-of-bounds in fbcon_set_font() (CVE-2023-3161)

    * kernel: out-of-bounds access in relay_file_read (CVE-2023-3268)

    * kernel: xfrm: NULL pointer dereference in xfrm_update_ae_params() (CVE-2023-3772)

    * kernel: xfrm: out-of-bounds read of XFRMA_MTIMER_THRESH nlattr (CVE-2023-3773)

    * kernel: KVM: SEV-ES / SEV-SNP VMGEXIT double fetch vulnerability (CVE-2023-4155)

    * kernel: exFAT: stack overflow in exfat_get_uniname_from_ext_entry (CVE-2023-4273)

    * kernel: mpls: double free on sysctl allocation failure (CVE-2023-26545)

    * kernel: KVM: nVMX: missing consistency checks for CR0 and CR4 (CVE-2023-30456)

    * kernel: net: qcom/emac: race condition leading to use-after-free in emac_remove() (CVE-2023-33203)

    * kernel: vmwgfx: race condition leading to information disclosure vulnerability (CVE-2023-33951)

    * kernel: vmwgfx: double free within the handling of vmw_buffer_object objects (CVE-2023-33952)

    * kernel: r592: race condition leading to use-after-free in r592_remove() (CVE-2023-35825)

    * kernel: net/tls: tls_is_tx_ready() checked list_entry (CVE-2023-1075)

    * kernel: tap: tap_open(): correctly initialize socket uid (CVE-2023-1076)

    * kernel: missing mmap_lock in file_files_note that could possibly lead to a use after free in the     coredump code (CVE-2023-1249)

    * kernel: use-after-free bug in remove function xgene_hwmon_remove (CVE-2023-1855)

    * kernel: Use after free bug in r592_remove (CVE-2023-3141)

    * kernel: gfs2: NULL pointer dereference in gfs2_evict_inode() (CVE-2023-3212)

    * kernel: NULL pointer dereference due to missing kalloc() return value check in     shtp_cl_get_dma_send_buf() (CVE-2023-3358)

    * kernel: tap: tap_open(): correctly initialize socket uid next fix of i_uid to current_fsuid     (CVE-2023-4194)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

    Additional Changes:

    For detailed information on changes in this release, see the Red Hat Enterprise Linux 9.3 Release Notes     linked from the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
352030	AlmaLinux 9.2 [TuxCare] Security Update: bpftool / kernel / kernel-abi-stablelists / kernel-core / etc Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2025:1765463110)	Nessus	Alma Linux Local Security Checks	Local	high
247218	Linux Distros Unpatched Vulnerability : CVE-2022-49882	Nessus	Misc.	Local	high
194262	RHEL 9 : kernel (RHSA-2023:6583)	Nessus	Red Hat Local Security Checks	Local	high

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