CVE-2026-53306
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: tty: hvc_iucv: fix off-by-one in number of supported devices MAX_HVC_IUCV_LINES == HVC_ALLOC_TTY_ADAPTERS == 8. This is the number of entries in: static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES]; Sometimes hvc_iucv_table[] is limited by: (a) if (num > hvc_iucv_devices) // for error detection or (b) for (i = 0; i < hvc_iucv_devices; i++) // in 2 places (so these 2 don't agree; second one appears to be correct to me.) hvc_iucv_devices can be 0..8. This is a counter. (c) if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) If hvc_iucv_devices == 8, (a) allows the code to access hvc_iucv_table[8]. Oops.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-06-26 20:17:23.877000
Last modified
2026-11-06 17:18:23.710000
View original CVE JSON
{
"id": "CVE-2026-53306",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-06-26T20:17:23.877",
"lastModified": "2026-11-06T17:18:23.710",
"vulnStatus": "Analyzed",
"cveTags": [],
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntty: hvc_iucv: fix off-by-one in number of supported devices\n\nMAX_HVC_IUCV_LINES == HVC_ALLOC_TTY_ADAPTERS == 8.\nThis is the number of entries in:\n static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES];\n\nSometimes hvc_iucv_table[] is limited by:\n(a)\tif (num > hvc_iucv_devices) // for error detection\nor\n(b)\tfor (i = 0; i < hvc_iucv_devices; i++) // in 2 places\n(so these 2 don't agree; second one appears to be correct to me.)\n\nhvc_iucv_devices can be 0..8. This is a counter.\n(c)\tif (hvc_iucv_devices > MAX_HVC_IUCV_LINES)\n\nIf hvc_iucv_devices == 8, (a) allows the code to access hvc_iucv_table[8].\nOops."
}
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"scope": "UNCHANGED",
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