{
  "cveId": "CVE-2026-89732",
  "url": "https://patchblox.com/security/cve/CVE-2026-89732",
  "summary": "CVE-2026-89732 is fixed in 12 products on 1 platform, first by DEBIAN-CVE-2026-89732, released September 23, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  usb: gadget: f_fs: Prevent deadlock during ep0 r...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  usb: gadget: f_fs: Prevent deadlock during ep0 read loop  Currently, ffs_ep0_read() holds ffs-\u003Emutex when it prepares to go to sleep waiting for an event. When no setup events are pending, it calls wait_event_interruptible_exclusive_locked_irq() with the mutex still held. The wait macro deliberately drops the waitqueue spinlock before sleeping but does not drop the mutex.  If a userspace daemon is polling ep0 via read() and the gadget is asynchronously torn down via configfs (e.g., echo \u0022\u0022 \u003E UDC), a deadlock can occur:  1. The configfs teardown calls functionfs_unbind(), which queues a    FUNCTIONFS_UNBIND event. 2. The daemon wakes up, consumes the event, and drops the mutex. 3. However, if the daemon loops and immediately issues another read()    before exiting, it reacquires ffs-\u003Emutex and again goes into an    interruptible sleep. 4. Meanwhile, functionfs_unbind() continues execution and attempts to    acquire ffs-\u003Emutex to tear down ep0req. 5. The kernel deadlocks because the configfs thread is stuck in an    uninterruptible sleep waiting for the mutex, while the userspace    daemon is in an interruptible sleep holding the mutex forever    because no more events will arrive.  To fix this, we drop both the waitqueue spinlock and ffs-\u003Emutex before going to sleep, and use wait_event_interruptible_exclusive() instead. Upon waking up, we jump back to the \u0060retry\u0060 label to safely reacquire the mutex and re-evaluate the state machine. By not sleeping with ffs-\u003Emutex held, we natively decouple gadget teardowns (which require the mutex) from userspace polling.",
  "published": "2026-09-11T20:20:03Z",
  "severity": "",
  "epss": 0.00233,
  "epssPercentile": 0.14242,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "kernel-64kb",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-azure",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-default",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-default-base",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1.150700.17.51.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-docs",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-livepatch-SLE15-SP7_Update_24",
      "release": "sles 15.7",
      "fixedVersion": "1-150700.15.3.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-obs-build",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-source",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-syms",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "kernel-zfcpdump",
      "release": "sles 15.7",
      "fixedVersion": "6.4.0-150700.53.90.1",
      "fix": "SUSE-SU-2026:5091-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-5091-1",
      "released": "2026-11-07T00:43:02Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.1.190-1",
      "fix": "DEBIAN-CVE-2026-89732",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89732",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.111-1",
      "fix": "DEBIAN-CVE-2026-89732",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89732",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-89732",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89732",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "linux-6.12",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.12.111-1~deb12u1",
      "fix": "DEBIAN-CVE-2026-89732",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89732",
      "released": "2026-09-23T19:19:02Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T01:18:40Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}