{"id":"CVE-2026-53306","title":"tty: hvc_iucv: fix off-by-one in number of supported devices","summary":"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_i…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff","Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 484357dff256c816d9466bda35eb765685e4dc86","Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 11207e42a332eb8bbcb9fe74df9edd2a807c5607","Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4","Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < a76511bc654819425d3b15e77b523d7f9d81f064","Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 3104a3f40feb107f77d7116ad9bf6c210ab7babf","Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < f1dc8e72de9aabe5d96767a4e97219ac26b79fe5","Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < f2a880e802ad12d1e38039d1334fb1475d0f5241","Linux 2.6.29"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:26:13.374243Z"},"published":"2026-06-26","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:34:19.674Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53306","references":[{"url":"https://git.kernel.org/stable/c/3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff"},{"url":"https://git.kernel.org/stable/c/484357dff256c816d9466bda35eb765685e4dc86"},{"url":"https://git.kernel.org/stable/c/11207e42a332eb8bbcb9fe74df9edd2a807c5607"},{"url":"https://git.kernel.org/stable/c/fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4"},{"url":"https://git.kernel.org/stable/c/a76511bc654819425d3b15e77b523d7f9d81f064"},{"url":"https://git.kernel.org/stable/c/3104a3f40feb107f77d7116ad9bf6c210ab7babf"},{"url":"https://git.kernel.org/stable/c/f1dc8e72de9aabe5d96767a4e97219ac26b79fe5"},{"url":"https://git.kernel.org/stable/c/f2a880e802ad12d1e38039d1334fb1475d0f5241"}],"tags":["cve.org"],"epss":0.00162,"epssPercentile":0.05467,"ingestedAt":"2026-11-06T16:57:43.250Z","slug":"CVE-2026-53306","body":"## Overview\n\nIn 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.\n\n## Affected\n\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff`\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 484357dff256c816d9466bda35eb765685e4dc86`\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 11207e42a332eb8bbcb9fe74df9edd2a807c5607`\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4`\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < a76511bc654819425d3b15e77b523d7f9d81f064`\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < 3104a3f40feb107f77d7116ad9bf6c210ab7babf`\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < f1dc8e72de9aabe5d96767a4e97219ac26b79fe5`\n- `Linux >= 44a01d5ba8a4d543694461cd3e178cfa6b3f221b < f2a880e802ad12d1e38039d1334fb1475d0f5241`\n- `Linux 2.6.29`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}