CyberSecBulletin

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 Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.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

  • 7.0 High severity

    Windows 10 Version 1809: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-27926Microsoft

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Cloud Files Mini Filter Driver allows an authorized attacker to elevate privileges locally.

  • 7.0 High severity

    Windows 10 Version 1607: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-27921MicrosoftEPSS 1.24%

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an authorized attacker to elevate privileges locally.

  • 7.8 High severity

    Windows 10 Version 1607: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-27911Microsoft

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows User Interface Core allows an authorized attacker to elevate privileges locally.

  • 7.0 High severity

    Windows 10 Version 1607: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-26174Microsoft

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Server Update Service allows an authorized attacker to elevate privileges locally.

  • 7.0 High severity

    Windows 10 Version 1607: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-26173Microsoft

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

  • 7.8 High severity

    Windows 10 Version 21H2: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-26172Microsoft

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Push Notifications allows an authorized attacker to elevate privileges locally.

  • 7.8 High severity

    Windows 10 Version 1607: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-26168Microsoft

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

  • 7.8 High severity

    Windows 10 Version 1607: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-26167Microsoft

    Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Push Notifications allows an authorized attacker to elevate privileges locally.

  • 7.8 High severity

    InDesign Desktop: Use After Free

    CVE-2026-27283Adobe

    InDesign Desktop versions 20.5.2, 21.2 and earlier are affected by a Use After Free vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open

  • 8.1 High severity

    CPython: Use After Free

    CVE-2026-6100Python Software Foundation

    Use-after-free (UAF) was possible in the `lzma.LZMADecompressor`, `bz2.BZ2Decompressor`, and `gzip.GzipFile` when a memory allocation fails with a `MemoryError` and the decompression instance is re-used. This scenario can be triggered if the process is under m

  • 8.4 High severity

    Nitro PDF Pro: Use After Free

    CVE-2025-69627Gonitro

    Nitro PDF Pro for Windows 14.41.1.4 contains a heap use-after-free vulnerability in the implementation of the JavaScript method this.mailDoc(). During execution, an internal XID object is allocated and then freed prematurely, after which the freed pointer is s

  • 7.0 High severity

    Linux: Use After Free

    CVE-2026-31426Linux

    In the Linux kernel, the following vulnerability has been resolved: ACPI: EC: clean up handlers on probe failure in acpi_ec_setup() When ec_install_handlers() returns -EPROBE_DEFER on reduced-hardware platforms, it has already started the EC and installed the

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-31419Linux

    In the Linux kernel, the following vulnerability has been resolved: net: bonding: fix use-after-free in bond_xmit_broadcast() bond_xmit_broadcast() reuses the original skb for the last slave (determined by bond_is_last_slave()) and clones it for others. Concur

  • 9.6 Critical severity

    NASM: Use After Free

    CVE-2026-6068Nasm

    NASM contains a heap use after free vulnerability in response file (-@) processing where a dangling pointer to freed memory is stored in the global depend_file and later dereferenced, as the response-file buffer is freed before the pointer is used, allowing fo

  • 7.8 High severity

    hdf5: Use After Free

    CVE-2026-34734Hdfgroup

    HDF5 is software for managing data. In 1.14.1-2 and earlier, a heap-use-after-free was found in the h5dump helper utility. An attacker who can supply a malicious h5 file can trigger a heap use-after-free. The freed object is referenced in a memmove call from H

  • 8.8 High severity

    Chrome: Use After Free

    CVE-2026-5883Google

    Use after free in Media in Google Chrome prior to 147.0.7727.55 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: Medium)

  • 8.8 High severity

    Chrome: Use After Free

    CVE-2026-5877Google

    Use after free in Navigation in Google Chrome prior to 147.0.7727.55 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: Medium)

  • 9.6 Critical severity

    Chrome: Use After Free

    CVE-2026-5874Google

    Use after free in PrivateAI in Google Chrome prior to 147.0.7727.55 allowed a remote attacker who convinced a user to engage in specific UI gestures to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: Medium)

  • 8.8 High severity

    Chrome: Use After Free

    CVE-2026-5872Google

    Use after free in Blink in Google Chrome prior to 147.0.7727.55 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)

  • 8.8 High severity

    Chrome: Use After Free

    CVE-2026-5866Google

    Use after free in Media in Google Chrome prior to 147.0.7727.55 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)

  • 8.8 High severity

    Chrome: Use After Free

    CVE-2026-5861Google

    Use after free in V8 in Google Chrome prior to 147.0.7727.55 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)

  • 8.8 High severity

    Chrome: Use After Free

    CVE-2026-5860Google

    Use after free in WebRTC in Google Chrome prior to 147.0.7727.55 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)

  • 8.1 High severity

    OpenSSL: Use After Free

    CVE-2026-28387OpenSSL

    Issue summary: An uncommon configuration of clients performing DANE TLSA-based server authentication, when paired with uncommon server DANE TLSA records, may result in a use-after-free and/or double-free on the client side. Impact summary: A use after free can

  • 8.7 High severity

    Apache Kafka Clients: Concurrent Execution using Shared Resource with Improper Synchronization

    CVE-2026-35554Apache

    A race condition in the Apache Kafka Java producer client’s buffer pool management can cause messages to be silently delivered to incorrect topics. When a produce batch expires due to delivery.timeout.ms while a network request containing that batch is still i

  • 8.8 High severity

    Linux: Use After Free

    CVE-2026-31408Linux

    In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: Fix use-after-free in sco_recv_frame() due to missing sock_hold sco_recv_frame() reads conn->sk under sco_conn_lock() but immediately releases the lock without holding a refere

  • 8.1 High severity

    electron: Use After Free

    CVE-2026-34774Electron

    Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 39.8.1, 40.7.0, and 41.0.0, apps that use offscreen rendering and allow child windows via window.open() may be vulnerable to a use-after-f

  • 8.8 High severity

    electron: Use After Free

    CVE-2026-34772Electron

    Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.0, 40.7.0, and 41.0.0-beta.8, apps that allow downloads and programmatically destroy sessions may be vulnerable to a use-afte

  • 8.8 High severity

    electron: Use After Free

    CVE-2026-34771Electron

    Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.0, 40.7.0, and 41.0.0-beta.8, apps that register an asynchronous session.setPermissionRequestHandler() may be vulnerable to a

  • 8.8 High severity

    electron: Use After Free

    CVE-2026-34770Electron

    Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.0, and 41.0.0-beta.8, apps that use the powerMonitor module may be vulnerable to a use-after-free. After the native P

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-31403Linux

    In the Linux kernel, the following vulnerability has been resolved: NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd The /proc/fs/nfs/exports proc entry is created at module init and persists for the module's lifetime. exports_proc_open() c

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-31399Linux

    In the Linux kernel, the following vulnerability has been resolved: nvdimm/bus: Fix potential use after free in asynchronous initialization Dingisoul with KASAN reports a use after free if device_add() fails in nd_async_device_register(). Commit b6eae0f61db2 (

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-31396Linux

    In the Linux kernel, the following vulnerability has been resolved: net: macb: fix use-after-free access to PTP clock PTP clock is registered on every opening of the interface and destroyed on every closing. However it may be accessed via get_ts_info ethtool c

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-31389Linux

    In the Linux kernel, the following vulnerability has been resolved: spi: fix use-after-free on controller registration failure Make sure to deregister from driver core also in the unlikely event that per-cpu statistics allocation fails during controller regist

  • 8.8 High severity

    Linux: Use After Free

    CVE-2026-23462Linux

    In the Linux kernel, the following vulnerability has been resolved: Bluetooth: HIDP: Fix possible UAF This fixes the following trace caused by not dropping l2cap_conn reference when user->remove callback is called: [ 97.809249] l2cap_conn_free: freeing conn ff

  • 8.8 High severity

    Linux: Use After Free

    CVE-2026-23461Linux

    In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del"), l2cap_conn_del() uses conn->lock to protect ac

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-23458Linux

    In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_ct() ctnetlink_dump_exp_ct() stores a conntrack pointer in cb->data for the netlink dump callback ctnetlink_exp_ct_dump_table(),

  • 7.0 High severity

    Linux: Use After Free

    CVE-2026-23454Linux

    In the Linux kernel, the following vulnerability has been resolved: net: mana: fix use-after-free in mana_hwc_destroy_channel() by reordering teardown A potential race condition exists in mana_hwc_destroy_channel() where hwc->caller_ctx is freed before the HWC

  • 9.8 Critical severity

    Linux: Use After Free

    CVE-2026-23450Linux

    In the Linux kernel, the following vulnerability has been resolved: net/smc: fix NULL dereference and UAF in smc_tcp_syn_recv_sock() Syzkaller reported a panic in smc_tcp_syn_recv_sock() [1]. smc_tcp_syn_recv_sock() is called in the TCP receive path (softirq)

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-23432Linux

    In the Linux kernel, the following vulnerability has been resolved: mshv: Fix use-after-free in mshv_map_user_memory error path In the error path of mshv_map_user_memory(), calling vfree() directly on the region leaves the MMU notifier registered. When userspa

  • 7.8 High severity

    Linux: Use After Free

    CVE-2026-23428Linux

    In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free of share_conf in compound request smb2_get_ksmbd_tcon() reuses work->tcon in compound requests without validating tcon->t_state. ksmbd_tree_conn_lookup() checks t_sta