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CVE-2026-64336

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: USB: serial: keyspan_pda: fix information leak The write() callback is supposed to return the number of characters accepted or a negative errno. Since the addition of write fifo support the keyspan_pda implementation will however return the number characters submitted to the device if the write urb is not already in use. If this number is larger than the number of characters passed to write(), the line discipline continues writing data from beyond the tty write buffer. Fix the information leak by making sure that keyspan_pda_write_start() returns zero on success as intended.

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-25 10:17:15.463000
Last modified
2026-11-06 17:18:49.220000
View original CVE JSON 
{
  "id": "CVE-2026-64336",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-25T10:17:15.463",
  "lastModified": "2026-11-06T17:18:49.220",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: serial: keyspan_pda: fix information leak\n\nThe write() callback is supposed to return the number of characters\naccepted or a negative errno. Since the addition of write fifo support\nthe keyspan_pda implementation will however return the number characters\nsubmitted to the device if the write urb is not already in use. If this\nnumber is larger than the number of characters passed to write(), the\nline discipline continues writing data from beyond the tty write buffer.\n\nFix the information leak by making sure that keyspan_pda_write_start()\nreturns zero on success as intended."
    }
  ],
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  "metrics": {
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          "privilegesRequired": "LOW",
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          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
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          "role": "CISA Coordinator",
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  "weaknesses": [
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      "source": "[email protected]",
      "type": "Primary",
      "description": [
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