{
  "threat_severity" : "Moderate",
  "public_date" : "2025-12-16T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Linux kernel: Denial of Service due to race condition in fbcon setup",
    "id" : "2422813",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2422813"
  },
  "cvss3" : {
    "cvss3_base_score" : "4.7",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-367",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\ndrm, fbcon, vga_switcheroo: Avoid race condition in fbcon setup\nProtect vga_switcheroo_client_fb_set() with console lock. Avoids OOB\naccess in fbcon_remap_all(). Without holding the console lock the call\nraces with switching outputs.\nVGA switcheroo calls fbcon_remap_all() when switching clients. The fbcon\nfunction uses struct fb_info.node, which is set by register_framebuffer().\nAs the fb-helper code currently sets up VGA switcheroo before registering\nthe framebuffer, the value of node is -1 and therefore not a legal value.\nFor example, fbcon uses the value within set_con2fb_map() [1] as an index\ninto an array.\nMoving vga_switcheroo_client_fb_set() after register_framebuffer() can\nresult in VGA switching that does not switch fbcon correctly.\nTherefore move vga_switcheroo_client_fb_set() under fbcon_fb_registered(),\nwhich already holds the console lock. Fbdev calls fbcon_fb_registered()\nfrom within register_framebuffer(). Serializes the helper with VGA\nswitcheroo's call to fbcon_remap_all().\nAlthough vga_switcheroo_client_fb_set() takes an instance of struct fb_info\nas parameter, it really only needs the contained fbcon state. Moving the\ncall to fbcon initialization is therefore cleaner than before. Only amdgpu,\ni915, nouveau and radeon support vga_switcheroo. For all other drivers,\nthis change does nothing.", "A flaw was found in the Linux kernel. A local user could exploit a race condition in the framebuffer console (fbcon) setup, specifically within the VGA switcheroo component. This race condition occurs when `vga_switcheroo_client_fb_set()` races with switching outputs, leading to an out-of-bounds (OOB) access in `fbcon_remap_all()`. This can result in a denial of service (DoS) to the system." ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "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" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2025-68296\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-68296\nhttps://lore.kernel.org/linux-cve-announce/2025121641-CVE-2025-68296-c946@gregkh/T" ],
  "name" : "CVE-2025-68296",
  "csaw" : false
}