Use After Free
CWE-416
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
We track 4,465 vulnerabilities of this type. 100% are rated high or critical, and the average CVSS score is 8.3. 109 have been exploited in real attacks.
How this weakness is prevented
- Architecture and Design: Choose a language that provides automatic memory management.
- Implementation: When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Latest Use After Free vulnerabilities
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: vrf: use RCU protection in l3mdev_l3_out() l3mdev_l3_out() can be called without RCU being held: raw_sendmsg() ip_push_pending_frames() ip_send_skb() ip_local_out() __ip_local_out() l3mdev_ip_
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: workqueue: Put the pwq after detaching the rescuer from the pool The commit 68f83057b913("workqueue: Reap workers via kthread_stop() and remove detach_completion") adds code to reap the normal
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ndisc: use RCU protection in ndisc_alloc_skb() ndisc_alloc_skb() can be called without RTNL or RCU being held. Add RCU protection to avoid possible UAF.
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: neighbour: use RCU protection in __neigh_notify() __neigh_notify() can be called without RTNL or RCU protection. Use RCU protection to avoid potential UAF.
- 8.1 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: arp: use RCU protection in arp_xmit() arp_xmit() can be called without RTNL or RCU protection. Use RCU protection to avoid potential UAF.
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: openvswitch: use RCU protection in ovs_vport_cmd_fill_info() ovs_vport_cmd_fill_info() can be called without RTNL or RCU. Use RCU protection and dev_net_rcu() to avoid potential UAF.
- 8.1 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ndisc: extend RCU protection in ndisc_send_skb() ndisc_send_skb() can be called without RTNL or RCU held. Acquire rcu_read_lock() earlier, so that we can use dev_net_rcu() and avoid a potentia
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: extend RCU protection in igmp6_send() igmp6_send() can be called without RTNL or RCU being held. Extend RCU protection so that we can safely fetch the net pointer and avoid a pote
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: vsock: Keep the binding until socket destruction Preserve sockets bindings; this includes both resulting from an explicit bind() and those implicitly bound through autobind during connect(). P
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix use-after-free when attempting to join an aborted transaction When we are trying to join the current transaction and if it's aborted, we read its 'aborted' field after unlocking fs_
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net/mlx5: HWS, change error flow on matcher disconnect Currently, when firmware failure occurs during matcher disconnect flow, the error flow of the function reconnects the matcher back and re
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Fix use-after free in init error and remove paths devm_blk_crypto_profile_init() registers a cleanup handler to run when the associated (platform-) device is being released. F
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Fix slab-use-after-free Read in mgmt_remove_adv_monitor_sync This fixes the following crash: ================================================================== BUG: KASAN: sla
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: media: uvcvideo: Remove dangling pointers When an async control is written, we copy a pointer to the file handle that started the operation. That pointer will be used when the device is done.
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: bsg: Set bsg_queue to NULL after removal Currently, this does not cause any issues, but I believe it is necessary to set bsg_queue to NULL after removing it to prevent potential use
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: drm/xe/tracing: Fix a potential TP_printk UAF The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move tr
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: nbd: don't allow reconnect after disconnect Following process can cause nbd_config UAF: 1) grab nbd_config temporarily; 2) nbd_genl_disconnect() flush all recv_work() and release the initial r
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: wifi: rtw89: fix race between cancel_hw_scan and hw_scan completion The rtwdev->scanning flag isn't protected by mutex originally, so cancel_hw_scan can pass the condition, but suddenly hw_sca
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: padata: fix UAF in padata_reorder A bug was found when run ltp test: BUG: KASAN: slab-use-after-free in padata_find_next+0x29/0x1a0 Read of size 4 at addr ffff88bbfe003524 by task kworker/u113
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: padata: avoid UAF for reorder_work Although the previous patch can avoid ps and ps UAF for _do_serial, it can not avoid potential UAF issue for reorder_work. This issue can happen just as belo
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: nilfs2: do not force clear folio if buffer is referenced Patch series "nilfs2: protect busy buffer heads from being force-cleared". This series fixes the buffer head state inconsistency issues
- 7.0 High severity
Linux: Concurrent Execution using Shared Resource with Improper Synchronization
In the Linux kernel, the following vulnerability has been resolved: net: rose: fix timer races against user threads Rose timers only acquire the socket spinlock, without checking if the socket is owned by one user thread. Add a check and rearm the timers if ne
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: davicom: fix UAF in dm9000_drv_remove dm is netdev private data and it cannot be used after free_netdev() call. Using dm after free_netdev() can cause UAF bug. Fix it by moving free_netde
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix implicit ODP use after free Prevent double queueing of implicit ODP mr destroy work by using __xa_cmpxchg() to make sure this is the only time we are destroying this specific mr
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix read pointer after free in ath12k_mac_assign_vif_to_vdev() In ath12k_mac_assign_vif_to_vdev(), if arvif is created on a different radio, it gets deleted from that radio throu
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: i3c: dw: Fix use-after-free in dw_i3c_master driver due to race condition In dw_i3c_common_probe, &master->hj_work is bound with dw_i3c_hj_work. And dw_i3c_master_irq_handler can call dw_i3c_m
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: pps: Fix a use-after-free On a board running ntpd and gpsd, I'm seeing a consistent use-after-free in sys_exit() from gpsd when rebooting: pps pps1: removed ------------[ cut here ]-----------
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: tty: goldfish: Fix free_irq() on remove Pass the correct dev_id to free_irq() to fix this splat when the driver is unbound: WARNING: CPU: 0 PID: 30 at kernel/irq/manage.c:1895 free_irq Trying
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: bus: fsl-mc-bus: fix KASAN use-after-free in fsl_mc_bus_remove() In fsl_mc_bus_remove(), mc->root_mc_bus_dev->mc_io is passed to fsl_destroy_mc_io(). However, mc->root_mc_bus_dev is already fr
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: mm/slub: add missing TID updates on slab deactivation The fastpath in slab_alloc_node() assumes that c->slab is stable as long as the TID stays the same. However, two places in __slab_alloc()
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: tipc: fix use-after-free Read in tipc_named_reinit syzbot found the following issue on: ================================================================== BUG: KASAN: use-after-free in tipc_na
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: igb: fix a use-after-free issue in igb_clean_tx_ring Fix the following use-after-free bug in igb_clean_tx_ring routine when the NIC is running in XDP mode. The issue can be triggered redirecti
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: block: disable the elevator int del_gendisk The elevator is only used for file system requests, which are stopped in del_gendisk. Move disabling the elevator and freeing the scheduler tags to
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: iio: trigger: sysfs: fix use-after-free on remove Ensure that the irq_work has completed before the trigger is freed. ================================================================== BUG: KA
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix race on unaccepted mptcp sockets When the listener socket owning the relevant request is closed, it frees the unaccepted subflows and that causes later deletion of the paired MPTCP
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: bonding: fix use-after-free after 802.3ad slave unbind commit 0622cab0341c ("bonding: fix 802.3ad aggregator reselection"), resolve case, when there is several aggregation groups in the s
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: srcu: Tighten cleanup_srcu_struct() GP checks Currently, cleanup_srcu_struct() checks for a grace period in progress, but it does not check for a grace period that has not yet started but whic
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: cgroup: Use separate src/dst nodes when preloading css_sets for migration Each cset (css_set) is pinned by its tasks. When we're moving tasks around across csets for a migration, we need to ho
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: sfc: fix use after free when disabling sriov Use after free is detected by kfence when disabling sriov. What was read after being freed was vf->pci_dev: it was freed from pci_disable_sriov and
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: avoid skb access on nf_stolen When verdict is NF_STOLEN, the skb might have been freed. When tracing is enabled, this can result in a use-after-free: 1. access to skb->nf