{
  "cveId": "CVE-2026-98838",
  "url": "https://patchblox.com/security/cve/CVE-2026-98838",
  "summary": "CVE-2026-98838 is fixed in 12 products on 1 platform, first by DEBIAN-CVE-2026-98838, released October 19, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "vt: skip screen update for DEC alignment test on backgroup consoles",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  vt: skip screen update for DEC alignment test on backgroup consoles  [BUG] Recently, we encountered a KASAN warning as follows:  BUG: KASAN: slab-out-of-bounds in fb_pad_aligned_buffer\u002B0x11f/0x140 Read of size 1 at addr ff1100015fd9f6a4 by task tty_fbcon_oob/1239 CPU: 7 UID: 0 PID: 1239 Comm: tty_fbcon_oob Not tainted 7.3.0-rc1 #100 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX \u002B PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 Call Trace:  \u003CTASK\u003E  ...  kasan_report\u002B0xf0/0x120  fb_pad_aligned_buffer\u002B0x11f/0x140  ccw_putcs\u002B0x86c/0xa80  fbcon_putcs\u002B0x338/0x410  do_update_region\u002B0x21d/0x450  do_con_write\u002B0x1e0e/0x4880  con_write\u002B0x13/0x80  n_tty_write\u002B0x374/0x1010  file_tty_write.isra.0\u002B0x404/0x7a0  ...  reproduce: 1) open /dev/tty0, set a KDFONTOP ioctl with op.op = KD_FONT_OP_SET, op.width = 8 and op.height = 16 (visible VC1) 2) open /dev/tty1, set a KDFONTOP ioctl with op.op = KD_FONT_OP_SET, op.width = 28 and op.height = 24 (invisible VC2) 3) echo 3 \u003E /sys/devices/virtual/graphics/fbcon/rotate_all 4) write EShash8(esc hash8) to tty1  [CAUSE] All VCs render to the framebuffer. setfont only modifies the target VC\u0027s font without resizing the framebuffer backing buffer (par-\u003Erotated.buf); the buffer is only resized for the visible VC (fbcon_do_set_font -\u003E ... -\u003E vc_do_resize -\u003E update_screen). This relies on the con_should_update() check performed before every update_region().  However, the ESC # 8 path (do_con_trol -\u003E do_update_region) omits the con_should_update() check. After changing the font size of an invisible VC, do_update_region() fills using the new font size against a buffer that was never resized, causing an out-of-bounds access.  [FIX] Only push the update when the console is visible and not blanked, add the con_should_update() check in the do_con_trol() like every other call site of do_update_region() (update_region(), invert_screen(), ...).",
  "published": "2026-10-18T16:17:38Z",
  "severity": "Moderate",
  "cvss": 4.1,
  "epss": 0.00177,
  "epssPercentile": 0.07301,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98838",
  "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 13.5 (trixie)",
      "fixedVersion": "6.12.113-1",
      "fix": "DEBIAN-CVE-2026-98838",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-98838",
      "released": "2026-10-19T16:27:52Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.10-1",
      "fix": "DEBIAN-CVE-2026-98838",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-98838",
      "released": "2026-10-19T16:27:52Z"
    },
    {
      "platform": "linux",
      "product": "linux-6.12",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.12.113-1~deb12u1",
      "fix": "DEBIAN-CVE-2026-98838",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-98838",
      "released": "2026-10-19T16:27:52Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T13:31:49Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}