fkie_cve-2025-39967
Vulnerability from fkie_nvd
Published
2025-10-15 08:15
Modified
2025-10-16 15:29
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: fbcon: fix integer overflow in fbcon_do_set_font Fix integer overflow vulnerabilities in fbcon_do_set_font() where font size calculations could overflow when handling user-controlled font parameters. The vulnerabilities occur when: 1. CALC_FONTSZ(h, pitch, charcount) performs h * pith * charcount multiplication with user-controlled values that can overflow. 2. FONT_EXTRA_WORDS * sizeof(int) + size addition can also overflow 3. This results in smaller allocations than expected, leading to buffer overflows during font data copying. Add explicit overflow checking using check_mul_overflow() and check_add_overflow() kernel helpers to safety validate all size calculations before allocation.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1a194e6c8e1ee745e914b0b7f50fa86c89ed13fe
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4a4bac869560f943edbe3c2b032062f6673b13d3
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/994bdc2d23c79087fbf7dcd9544454e8ebcef877
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/9c8ec14075c5317edd6b242f1be8167aa1e4e333
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a6eb9f423b3db000aaedf83367b8539f6b72dcfc
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/adac90bb1aaf45ca66f9db8ac100be16750ace78
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b8a6e85328aeb9881531dbe89bcd2637a06c3c95
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c0c01f9aa08c8e10e10e8c9ebb5be01a4eff6eb7
Impacted products
Vendor Product Version


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{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfbcon: fix integer overflow in fbcon_do_set_font\n\nFix integer overflow vulnerabilities in fbcon_do_set_font() where font\nsize calculations could overflow when handling user-controlled font\nparameters.\n\nThe vulnerabilities occur when:\n1. CALC_FONTSZ(h, pitch, charcount) performs h * pith * charcount\n   multiplication with user-controlled values that can overflow.\n2. FONT_EXTRA_WORDS * sizeof(int) + size addition can also overflow\n3. This results in smaller allocations than expected, leading to buffer\n   overflows during font data copying.\n\nAdd explicit overflow checking using check_mul_overflow() and\ncheck_add_overflow() kernel helpers to safety validate all size\ncalculations before allocation."
    }
  ],
  "id": "CVE-2025-39967",
  "lastModified": "2025-10-16T15:29:11.563",
  "metrics": {},
  "published": "2025-10-15T08:15:34.210",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1a194e6c8e1ee745e914b0b7f50fa86c89ed13fe"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4a4bac869560f943edbe3c2b032062f6673b13d3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/994bdc2d23c79087fbf7dcd9544454e8ebcef877"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/9c8ec14075c5317edd6b242f1be8167aa1e4e333"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a6eb9f423b3db000aaedf83367b8539f6b72dcfc"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/adac90bb1aaf45ca66f9db8ac100be16750ace78"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b8a6e85328aeb9881531dbe89bcd2637a06c3c95"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c0c01f9aa08c8e10e10e8c9ebb5be01a4eff6eb7"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}


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