Double Free
CWE-415
The product calls free() twice on the same memory address.
We track 348 vulnerabilities of this type. 100% are rated high or critical, and the average CVSS score is 8.0. 6 have been exploited in real attacks.
How this weakness is prevented
- Architecture and Design: Choose a language that provides automatic memory management.
- Implementation: Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
- Implementation: Use a static analysis tool to find double free instances.
Latest Double Free vulnerabilities
- 8.1 High severity
zephyr: Double Free
The Zephyr net_buf library (lib/net_buf/buf.c) manipulated both of its reference counts -- the per-header buf->ref and the per-data-block ref_count at the start of each variable/heap data allocation -- with plain non-atomic C operators (buf->ref++, if (--buf->
- 7.5 High severity
Red Hat Enterprise Linux 10: Double Free
A double free issue has been identified in libarchive's RAR5 reader. During parsing of a specially crafted RAR5 archive, the filtered_buf pointer may remain stale after being freed during unpacking state reinitialization. Subsequent processing of another archi
- 8.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: vfio/pci: Clean up DMABUFs before disabling function On device shutdown, make vfio_pci_core_close_device() call vfio_pci_dma_buf_cleanup() before the function is disabled via vfio_pci_core_dis
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: mailbox: mailbox-test: don't free the reused channel The RX channel can be aliased to the TX channel if it has a different MMIO. This special case needs to be handled when freeing the channels
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: idpf: fix double free and use-after-free in aux device error paths When auxiliary_device_add() fails in idpf_plug_vport_aux_dev() or idpf_plug_core_aux_dev(), the err_aux_dev_add label calls a
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: netdev: fix double-free in netdev_nl_bind_rx_doit() Sashiko flags that genlmsg_reply() always consumes the skb. The error path calls nlmsg_free(rsp) so we can't jump directly to it. Let's not
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-ep-msi: Fix error unwind and prevent double alloc pci_epf_alloc_doorbell() stores the allocated doorbell message array in epf->db_msg/epf->num_db before requesting MSI vecto
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: ice: fix double-free of tx_buf skb If ice_tso() or ice_tx_csum() fail, the error path in ice_xmit_frame_ring() frees the skb, but the 'first' tx_buf still points to it and is marked as valid (
- 9.8 Critical severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: tipc: fix double-free in tipc_buf_append() tipc_msg_validate() can potentially reallocate the skb it is validating, freeing the old one. In tipc_buf_append(), it was being called with a pointe
- 7.5 High severity
Eclipse ThreadX - NetX Duo: Incomplete Cleanup
The security fix for CVE-2025-0728 in eclipse-threadx NetX Duo refactors error handling in the HTTP server PUT process to use a shared cleanup label, but this unified cleanup path unconditionally calls fx_file_close() even when the file was never successfully
- 8.8 High severity
aws-c-http: Double Free
Improper handling of HPACK dynamic table size updates in the AWS Common Runtime aws-c-http library might allow a remote threat actor operating a server to cause memory corruption on a connecting client application, potentially leading to arbitrary code executi
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: mm/alloc_tag: clear codetag for pages allocated before page_ext initialization Due to initialization ordering, page_ext is allocated and initialized relatively late during boot. Some pages hav
- 8.8 High severity
FreeRDP: Double Free
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, FreeRDP's RDPEAR NDR parser accepts one non-null NDR pointer ref-id for multiple logical pointer fields without tracking the pointed object's expected NDR type or ownership. When
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: RDMA/vmw_pvrdma: Fix double free on pvrdma_alloc_ucontext() error path Sashiko points out that pvrdma_uar_free() is already called within pvrdma_dealloc_ucontext(), so calling it before trigge
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: mm/damon/sysfs-schemes: protect path kfree() with damon_sysfs_lock damon_sysfs_quot_goal->path can be read and written by users, via DAMON sysfs 'path' file. It can also be indirectly read, fo
- 7.0 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix double free in create_space_info_sub_group() error path When kobject_init_and_add() fails, the call chain is: create_space_info_sub_group() -> btrfs_sysfs_add_space_info_type() -> k
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: ice: fix double free in ice_sf_eth_activate() error path When auxiliary_device_add() fails, ice_sf_eth_activate() jumps to aux_dev_uninit and calls auxiliary_device_uninit(&sf_dev->adev). The
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix double free in create_space_info() error path When kobject_init_and_add() fails, the call chain is: create_space_info() -> btrfs_sysfs_add_space_info_type() -> kobject_init_and_add(
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: ext4: fix dirtyclusters double decrement on fs shutdown fstests test generic/388 occasionally reproduces a warning in ext4_put_super() associated with the dirty clusters count: WARNING: CPU: 7
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: net: hns3: fix double free issue for tx spare buffer In hns3_set_ringparam(), a temporary copy (tmp_rings) of the ring structure is created for rollback. However, the tx_spare pointer in the o
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Fix double free in rxe_srq_from_init In rxe_srq_from_init(), the queue pointer 'q' is assigned to 'srq->rq.queue' before copying the SRQ number to user space. If copy_to_user() fails
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: net/rds: reset op_nents when zerocopy page pin fails When iov_iter_get_pages2() fails in rds_message_zcopy_from_user(), the pinned pages are released with put_page(), and rm->data.op_mmp_znoti
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: spi: rockchip-sfc: Fix double-free in remove() callback The driver uses devm_spi_register_controller() for registration, which automatically unregisters the controller via devm cleanup when th
- 9.8 Critical severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Completely fix fcport double free In qla24xx_els_dcmd_iocb() sp->free is set to qla2x00_els_dcmd_sp_free(). When an error happens, this function is called by qla2x00_sp_release(
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: cpufreq: governor: fix double free in cpufreq_dbs_governor_init() error path When kobject_init_and_add() fails, cpufreq_dbs_governor_init() calls kobject_put(&dbs_data->attr_set.kobj). The kob
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: dm: clear cloned request bio pointer when last clone bio completes Stale rq->bio values have been observed to cause double-initialization of cloned bios in request-based device-mapper targets,
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: net: mana: Fix double destroy_workqueue on service rescan PCI path While testing corner cases in the driver, a use-after-free crash was found on the service rescan PCI path. When mana_serv_res
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Fix RSS context delete logic We need to free the corresponding RSS context VNIC in FW everytime an RSS context is deleted in driver. Commit 667ac333dbb7 added a check to delete the VN
- 8.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: 9p/xen: protect xen_9pfs_front_free against concurrent calls The xenwatch thread can race with other back-end change notifications and call xen_9pfs_front_free() twice, hitting the observed ge
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: soc: ti: pruss: Fix double free in pruss_clk_mux_setup() In the pruss_clk_mux_setup(), the devm_add_action_or_reset() indirectly calls pruss_of_free_clk_provider(), which calls of_node_put(clk
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: procfs: fix possible double mmput() in do_procmap_query() When user provides incorrectly sized buffer for build ID for PROCMAP_QUERY we return with -ENAMETOOLONG error. After recent changes th
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: RDMA/umem: Fix double dma_buf_unpin in failure path In ib_umem_dmabuf_get_pinned_with_dma_device(), the call to ib_umem_dmabuf_map_pages() can fail. If this occurs, the dmabuf is immediately u
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Fix double free related to rereg_user_mr If IB_MR_REREG_TRANS is set during rereg_user_mr, the umem will be released and a new one will be allocated in irdma_rereg_mr_trans. If any
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: PCI: hv: Fix double ida_free in hv_pci_probe error path If hv_pci_probe() fails after storing the domain number in hbus->bridge->domain_nr, there is a call to free this domain_nr via pci_bus_r
- 8.8 High severity
Apache HTTP Server: Double Free
Double Free and possible RCE vulnerability in Apache HTTP Server with the HTTP/2 protocol. This issue affects Apache HTTP Server: 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.
- 9.8 Critical severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: net/x25: Fix potential double free of skb When alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at line 48 and returns 1 (error). This error propagates back through the call chain
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: accel/qaic: Handle DBC deactivation if the owner went away When a DBC is released, the device sends a QAIC_TRANS_DEACTIVATE_FROM_DEV transaction to the host over the QAIC_CONTROL MHI channel.
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: usb: ulpi: fix double free in ulpi_register_interface() error path When device_register() fails, ulpi_register() calls put_device() on ulpi->dev. The device release callback ulpi_dev_release()
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: reset: gpio: fix double free in reset_add_gpio_aux_device() error path When __auxiliary_device_add() fails, reset_add_gpio_aux_device() calls auxiliary_device_uninit(adev). The device release
- 7.8 High severity
Linux: Double Free
In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: possible double-free of cctx->remote_heap fastrpc_init_create_static_process() may free cctx->remote_heap on the err_map path but does not clear the pointer. Later, fastrpc_rpms