{
  "threat_severity" : "Low",
  "public_date" : "2025-09-16T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: mISDN: hfcpci: Fix warning when deleting uninitialized timer",
    "id" : "2395802",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2395802"
  },
  "cvss3" : {
    "cvss3_base_score" : "4.4",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-665",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nmISDN: hfcpci: Fix warning when deleting uninitialized timer\nWith CONFIG_DEBUG_OBJECTS_TIMERS unloading hfcpci module leads\nto the following splat:\n[  250.215892] ODEBUG: assert_init not available (active state 0) object: ffffffffc01a3dc0 object type: timer_list hint: 0x0\n[  250.217520] WARNING: CPU: 0 PID: 233 at lib/debugobjects.c:612 debug_print_object+0x1b6/0x2c0\n[  250.218775] Modules linked in: hfcpci(-) mISDN_core\n[  250.219537] CPU: 0 UID: 0 PID: 233 Comm: rmmod Not tainted 6.17.0-rc2-g6f713187ac98 #2 PREEMPT(voluntary)\n[  250.220940] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[  250.222377] RIP: 0010:debug_print_object+0x1b6/0x2c0\n[  250.223131] Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 41 56 48 8b 14 dd a0 4e 01 9f 48 89 ee 48 c7 c7 20 46 01 9f e8 cb 84d\n[  250.225805] RSP: 0018:ffff888015ea7c08 EFLAGS: 00010286\n[  250.226608] RAX: 0000000000000000 RBX: 0000000000000005 RCX: ffffffff9be93a95\n[  250.227708] RDX: 1ffff1100d945138 RSI: 0000000000000008 RDI: ffff88806ca289c0\n[  250.228993] RBP: ffffffff9f014a00 R08: 0000000000000001 R09: ffffed1002bd4f39\n[  250.230043] R10: ffff888015ea79cf R11: 0000000000000001 R12: 0000000000000001\n[  250.231185] R13: ffffffff9eea0520 R14: 0000000000000000 R15: ffff888015ea7cc8\n[  250.232454] FS:  00007f3208f01540(0000) GS:ffff8880caf5a000(0000) knlGS:0000000000000000\n[  250.233851] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[  250.234856] CR2: 00007f32090a7421 CR3: 0000000004d63000 CR4: 00000000000006f0\n[  250.236117] Call Trace:\n[  250.236599]  <TASK>\n[  250.236967]  ? trace_irq_enable.constprop.0+0xd4/0x130\n[  250.237920]  debug_object_assert_init+0x1f6/0x310\n[  250.238762]  ? __pfx_debug_object_assert_init+0x10/0x10\n[  250.239658]  ? __lock_acquire+0xdea/0x1c70\n[  250.240369]  __try_to_del_timer_sync+0x69/0x140\n[  250.241172]  ? __pfx___try_to_del_timer_sync+0x10/0x10\n[  250.242058]  ? __timer_delete_sync+0xc6/0x120\n[  250.242842]  ? lock_acquire+0x30/0x80\n[  250.243474]  ? __timer_delete_sync+0xc6/0x120\n[  250.244262]  __timer_delete_sync+0x98/0x120\n[  250.245015]  HFC_cleanup+0x10/0x20 [hfcpci]\n[  250.245704]  __do_sys_delete_module+0x348/0x510\n[  250.246461]  ? __pfx___do_sys_delete_module+0x10/0x10\n[  250.247338]  do_syscall_64+0xc1/0x360\n[  250.247924]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\nFix this by initializing hfc_tl timer with DEFINE_TIMER macro.\nAlso, use mod_timer instead of manual timeout update." ],
  "statement" : "The hfcpci driver could attempt to delete an uninitialized timer during module unload, triggering debug warnings and a possible crash on debug builds. The fix initializes the timer with DEFINE_TIMER() and uses mod_timer() instead of manually manipulating expires. This is a low-risk, local issue requiring privileged access and primarily affects unload/debug paths rather than normal runtime.",
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2025-39833\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-39833\nhttps://lore.kernel.org/linux-cve-announce/2025091657-CVE-2025-39833-c2ef@gregkh/T" ],
  "name" : "CVE-2025-39833",
  "csaw" : false
}