{"id":"CVE-2026-53306","state":"PUBLISHED","title":"tty: hvc_iucv: fix off-by-one in number of supported devices","description":"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.","publishedAt":"2026-06-26T19:41:01.338Z","updatedAt":"2026-06-26T19:41:01.338Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"484357dff256c816d9466bda35eb765685e4dc86","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"11207e42a332eb8bbcb9fe74df9edd2a807c5607","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"a76511bc654819425d3b15e77b523d7f9d81f064","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"3104a3f40feb107f77d7116ad9bf6c210ab7babf","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"f1dc8e72de9aabe5d96767a4e97219ac26b79fe5","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"f2a880e802ad12d1e38039d1334fb1475d0f5241","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/hvc/hvc_iucv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.29","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.29","versionType":"semver"},{"version":"5.10.258","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.209","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.141","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/hvc/hvc_iucv.c"]}],"references":["https://git.kernel.org/stable/c/3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff","https://git.kernel.org/stable/c/484357dff256c816d9466bda35eb765685e4dc86","https://git.kernel.org/stable/c/11207e42a332eb8bbcb9fe74df9edd2a807c5607","https://git.kernel.org/stable/c/fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4","https://git.kernel.org/stable/c/a76511bc654819425d3b15e77b523d7f9d81f064","https://git.kernel.org/stable/c/3104a3f40feb107f77d7116ad9bf6c210ab7babf","https://git.kernel.org/stable/c/f1dc8e72de9aabe5d96767a4e97219ac26b79fe5","https://git.kernel.org/stable/c/f2a880e802ad12d1e38039d1334fb1475d0f5241"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53306.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53306","state":"PUBLISHED","datePublished":"2026-06-26T19:41:01.338Z","dateUpdated":"2026-06-26T19:41:01.338Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-06-09T07:44:35.397Z"},"containers":{"cna":{"title":"tty: hvc_iucv: fix off-by-one in number of supported devices","descriptions":[{"lang":"en","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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"484357dff256c816d9466bda35eb765685e4dc86","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"11207e42a332eb8bbcb9fe74df9edd2a807c5607","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"a76511bc654819425d3b15e77b523d7f9d81f064","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"3104a3f40feb107f77d7116ad9bf6c210ab7babf","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"f1dc8e72de9aabe5d96767a4e97219ac26b79fe5","versionType":"git"},{"version":"44a01d5ba8a4d543694461cd3e178cfa6b3f221b","status":"affected","lessThan":"f2a880e802ad12d1e38039d1334fb1475d0f5241","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/hvc/hvc_iucv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.29","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.29","versionType":"semver"},{"version":"5.10.258","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.209","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.141","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/hvc/hvc_iucv.c"]}],"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"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-06-26T19:41:01.338Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"5.10.258"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"5.15.209"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.6.141"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.12.91"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.18.33"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"7.0.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}