{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98840", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.373Z", "datePublished": "2026-10-18T15:50:14.029Z", "dateUpdated": "2026-10-21T12:57:25.411Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:57:25.411Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvc_screen: reload vc pointer before if (ret) in vcs_write() to avoid UAF\n\nThe reload of 'vc' added by commit 8fb9ea65c9d1 (\"vc_screen: reload load\nof struct vc_data pointer in vcs_write() to avoid UAF\") sits after the\n'if (ret)' block, so the copy-failure break path exits the loop without\nreloading vc. If the vc was kfree()'d via vc_port_destruct during the\nunlocked copy_from_user() window, the post-loop\n'if (written && vc) vcs_scr_updated(vc)' is reached with a stale\nnon-NULL vc. The '&& vc' guard from commit a287620312dc (\"vc_screen:\nfix null-ptr-deref in vcs_notifier() during concurrent vcs_write\") only\nhandles the NULL case, not this stale-non-NULL case; vcs_notifier() then\nreads param->vc->vc_num from freed memory:\n\n BUG: KASAN: slab-use-after-free in vcs_notifier+0x7c/0xd0\n Read of size 2 at addr ffff888007149190\n Call Trace:\n vcs_notifier+0x7c/0xd0\n atomic_notifier_call_chain+0x70/0xa0\n vcs_scr_updated+0x77/0xa0\n vcs_write+0x71b/0x7e0\n Allocated by task: vc_allocate -> con_install -> tty_open\n Freed by task: kfree <- vt_ioctl (VT_DISALLOCATE -> vc_port_destruct)\n\nMove the reload to immediately after console_lock(), before 'if (ret)',\nso every break path below passes a fresh vc to the post-loop\nvcs_scr_updated()." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/tty/vt/vc_screen.c" ], "versions": [ { "version": "8232fca738011ca2ec865b46ec721d1796dc0580", "lessThan": "c073d01f6f5367c3a4f07efd507274ed0d03acd0", "status": "affected", "versionType": "git" }, { "version": "73049768ad57145acd337102c5aa3c788e6642c8", "lessThan": "1485a3dd97ab1af2605243cabe6b604546d46dd1", "status": "affected", "versionType": "git" }, { "version": "7cc3dd79777f6ae4625ec37e84dd18a26dc88bde", "lessThan": "233a2e190b12884d186027d0b86d43a48799b69c", "status": "affected", "versionType": "git" }, { "version": "a287620312dc6dcb9a093417a0e589bf30fcf38a", "lessThan": "9dfcadc5e003fb250dd471db90144bd5366140e9", "status": "affected", "versionType": "git" }, { "version": "a287620312dc6dcb9a093417a0e589bf30fcf38a", "lessThan": "226bd5603371cd9f6642cbb9e9a677f445de3530", "status": "affected", "versionType": "git" }, { "version": "43a6281790273c1b0a9ab76609ff0245b968f1e6", "status": "affected", "versionType": "git" }, { "version": "b6bbb85cf45bf0b070e741997fe0af3a772c5ad5", "status": "affected", "versionType": "git" }, { "version": "ff4806202749a51938236214adc0281481a57366", "status": "affected", "versionType": "git" }, { "version": "74be188eb2dc1c99d63986167b9a67d415fe7326", "status": "affected", "versionType": "git" }, { "version": "09a43e81279b8da15526da09877134b8bcf618b0", "status": "affected", "versionType": "git" }, { "version": "6.6.144", "lessThan": "6.6.160", "status": "affected", "versionType": "semver" }, { "version": "6.12.95", "lessThan": "6.12.113", "status": "affected", "versionType": "semver" }, { "version": "6.18.37", "lessThan": "6.18.56", "status": "affected", "versionType": "semver" }, { "version": "5.10.260", "lessThan": "5.11", "status": "affected", "versionType": "semver" }, { "version": "5.15.211", "lessThan": "5.16", "status": "affected", "versionType": "semver" }, { "version": "6.1.177", "lessThan": "6.2", "status": "affected", "versionType": "semver" }, { "version": "7.0.14", "lessThan": "7.1", "status": "affected", "versionType": "semver" }, { "version": "7.1.2", "lessThan": "7.2", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/tty/vt/vc_screen.c" ], "versions": [ { "version": "7.2", "status": "affected" }, { "version": "0", "lessThan": "7.2", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.113", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.56", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.10", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.144", "versionEndExcluding": "6.6.160" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.95", "versionEndExcluding": "6.12.113" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.37", "versionEndExcluding": "6.18.56" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.2", "versionEndExcluding": "7.2.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.2", "versionEndExcluding": "7.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.260" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.211" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.177" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0.14" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c073d01f6f5367c3a4f07efd507274ed0d03acd0" }, { "url": "https://git.kernel.org/stable/c/1485a3dd97ab1af2605243cabe6b604546d46dd1" }, { "url": "https://git.kernel.org/stable/c/233a2e190b12884d186027d0b86d43a48799b69c" }, { "url": "https://git.kernel.org/stable/c/9dfcadc5e003fb250dd471db90144bd5366140e9" }, { "url": "https://git.kernel.org/stable/c/226bd5603371cd9f6642cbb9e9a677f445de3530" } ], "title": "vc_screen: reload vc pointer before if (ret) in vcs_write() to avoid UAF", 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