ghsa-xjw8-49g8-mg8p
Vulnerability from github
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.
{
"affected": [],
"aliases": [
"CVE-2025-39967"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-10-15T08:15:34Z",
"severity": null
},
"details": "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": "GHSA-xjw8-49g8-mg8p",
"modified": "2025-10-15T09:30:16Z",
"published": "2025-10-15T09:30:16Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39967"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1a194e6c8e1ee745e914b0b7f50fa86c89ed13fe"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4a4bac869560f943edbe3c2b032062f6673b13d3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/994bdc2d23c79087fbf7dcd9544454e8ebcef877"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9c8ec14075c5317edd6b242f1be8167aa1e4e333"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a6eb9f423b3db000aaedf83367b8539f6b72dcfc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/adac90bb1aaf45ca66f9db8ac100be16750ace78"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b8a6e85328aeb9881531dbe89bcd2637a06c3c95"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c0c01f9aa08c8e10e10e8c9ebb5be01a4eff6eb7"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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- Confirmed: The vulnerability is confirmed from an analyst perspective.
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- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.