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… (CVE-2026-53306)
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.
AI Analysis
Technical Summary
This vulnerability involves an off-by-one error in the tty: hvc_iucv component affecting Microsoft software version 3.0. The issue concerns the incorrect handling of the number of supported devices, which may lead to unexpected behavior. No further technical details, exploitation methods, or impact specifics are provided in the available data.
Potential Impact
The impact of this vulnerability is not explicitly described in the provided information. Without details on exploitation or consequences, the exact risk to affected systems cannot be determined from the current data.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround information is provided at this time.
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… (CVE-2026-53306)
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.
CVSS v3.1
Score 5.5medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves an off-by-one error in the tty: hvc_iucv component affecting Microsoft software version 3.0. The issue concerns the incorrect handling of the number of supported devices, which may lead to unexpected behavior. No further technical details, exploitation methods, or impact specifics are provided in the available data.
Potential Impact
The impact of this vulnerability is not explicitly described in the provided information. Without details on exploitation or consequences, the exact risk to affected systems cannot be determined from the current data.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround information is provided at this time.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_vex
- Csaf Version
- 2.0
- Publisher
- Microsoft Security Response Center
- Advisory Id
- msrc_CVE-2026-53306
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- 3.1
Threat ID: 6a483cbc27e9c79719d83403
Added to database: 07/03/2026, 22:50:36 UTC
Last enriched: 07/03/2026, 23:07:07 UTC
Last updated: 07/31/2026, 19:24:49 UTC
Views: 23
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