{"api_version":"1","generated_at":"2026-10-21T03:22:38+00:00","cve":"CVE-2026-98584","urls":{"html":"https://cve.report/CVE-2026-98584","api":"https://cve.report/api/cve/CVE-2026-98584.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98584","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98584"},"summary":{"title":"net/sched: fix potential stack infoleak in em_text_dump()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fix potential stack infoleak in em_text_dump()\n\nem_text_dump() allocates struct tcf_em_text on the stack without zeroing\nit.  strscpy() writes the algorithm name and a NUL terminator into\nconf.algo[], leaving the remaining bytes uninitialised.  nla_put_nohdr()\nthen copies the full struct to the netlink response.\n\nKMSAN on Linux 7.2-rc6 reports two kernel-infoleak splats from this path,\none triggered via \"tc filter show\" and one via a raw RTM_GETTFILTER dump:\n\n  BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x1c9/0x2620\n    nla_put_nohdr+0x83/0x130\n    em_text_dump+0x291/0x550\n  Local variable conf created at: em_text_dump+0x5d/0x550\n  Bytes 168-179 of 199 are uninitialized\n\nI am not certain whether this constitutes a real security problem in\npractice: the test was conducted in a controlled KMSAN environment and\nthe leaked stack bytes may or may not carry sensitive data on actual\nproduction kernels.  I am reporting it because KMSAN flagged it as a\nkernel-infoleak and the fix is straightforward.  I can provide a\nuserspace reproducer on request.\n\nThe original code used strncpy() which zero-pads to the destination size.\nCommit b04202d6065c (\"net/sched: replace strncpy with strscpy\") replaced\nit with strscpy(), which does not pad, creating this condition.\nZero-initialising the struct closes it.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-18 16:17:10","updated_at":"2026-10-19 10:19:19"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/9923e1c537f91f3530b52d4efce85f3d9c131bf8","name":"https://git.kernel.org/stable/c/9923e1c537f91f3530b52d4efce85f3d9c131bf8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0b160417826d22f24fc31a5b9cfae3b14aa70f76","name":"https://git.kernel.org/stable/c/0b160417826d22f24fc31a5b9cfae3b14aa70f76","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9c572a83037a7dcd653ba3a9cc468c16b857d0c9","name":"https://git.kernel.org/stable/c/9c572a83037a7dcd653ba3a9cc468c16b857d0c9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98584","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98584","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b04202d6065cba5dfd51fb9866400b25573eac67 9923e1c537f91f3530b52d4efce85f3d9c131bf8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b04202d6065cba5dfd51fb9866400b25573eac67 0b160417826d22f24fc31a5b9cfae3b14aa70f76 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b04202d6065cba5dfd51fb9866400b25573eac67 9c572a83037a7dcd653ba3a9cc468c16b857d0c9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.17","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.17 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.55 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.9 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/sched/em_text.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"9923e1c537f91f3530b52d4efce85f3d9c131bf8","status":"affected","version":"b04202d6065cba5dfd51fb9866400b25573eac67","versionType":"git"},{"lessThan":"0b160417826d22f24fc31a5b9cfae3b14aa70f76","status":"affected","version":"b04202d6065cba5dfd51fb9866400b25573eac67","versionType":"git"},{"lessThan":"9c572a83037a7dcd653ba3a9cc468c16b857d0c9","status":"affected","version":"b04202d6065cba5dfd51fb9866400b25573eac67","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/sched/em_text.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.17"},{"lessThan":"6.17","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.55","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.9","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.55","versionStartIncluding":"6.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.9","versionStartIncluding":"6.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"6.17","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fix potential stack infoleak in em_text_dump()\n\nem_text_dump() allocates struct tcf_em_text on the stack without zeroing\nit.  strscpy() writes the algorithm name and a NUL terminator into\nconf.algo[], leaving the remaining bytes uninitialised.  nla_put_nohdr()\nthen copies the full struct to the netlink response.\n\nKMSAN on Linux 7.2-rc6 reports two kernel-infoleak splats from this path,\none triggered via \"tc filter show\" and one via a raw RTM_GETTFILTER dump:\n\n  BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x1c9/0x2620\n    nla_put_nohdr+0x83/0x130\n    em_text_dump+0x291/0x550\n  Local variable conf created at: em_text_dump+0x5d/0x550\n  Bytes 168-179 of 199 are uninitialized\n\nI am not certain whether this constitutes a real security problem in\npractice: the test was conducted in a controlled KMSAN environment and\nthe leaked stack bytes may or may not carry sensitive data on actual\nproduction kernels.  I am reporting it because KMSAN flagged it as a\nkernel-infoleak and the fix is straightforward.  I can provide a\nuserspace reproducer on request.\n\nThe original code used strncpy() which zero-pads to the destination size.\nCommit b04202d6065c (\"net/sched: replace strncpy with strscpy\") replaced\nit with strscpy(), which does not pad, creating this condition.\nZero-initialising the struct closes it."}],"providerMetadata":{"dateUpdated":"2026-10-19T09:22:09.980Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/9923e1c537f91f3530b52d4efce85f3d9c131bf8"},{"url":"https://git.kernel.org/stable/c/0b160417826d22f24fc31a5b9cfae3b14aa70f76"},{"url":"https://git.kernel.org/stable/c/9c572a83037a7dcd653ba3a9cc468c16b857d0c9"}],"title":"net/sched: fix potential stack infoleak in em_text_dump()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98584","datePublished":"2026-10-18T15:18:57.204Z","dateReserved":"2026-09-25T10:25:14.358Z","dateUpdated":"2026-10-19T09:22:09.980Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-18 16:17:10","lastModifiedDate":"2026-10-19 10:19:19","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98584","Ordinal":"1","Title":"net/sched: fix potential stack infoleak in em_text_dump()","CVE":"CVE-2026-98584","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98584","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fix potential stack infoleak in em_text_dump()\n\nem_text_dump() allocates struct tcf_em_text on the stack without zeroing\nit.  strscpy() writes the algorithm name and a NUL terminator into\nconf.algo[], leaving the remaining bytes uninitialised.  nla_put_nohdr()\nthen copies the full struct to the netlink response.\n\nKMSAN on Linux 7.2-rc6 reports two kernel-infoleak splats from this path,\none triggered via \"tc filter show\" and one via a raw RTM_GETTFILTER dump:\n\n  BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x1c9/0x2620\n    nla_put_nohdr+0x83/0x130\n    em_text_dump+0x291/0x550\n  Local variable conf created at: em_text_dump+0x5d/0x550\n  Bytes 168-179 of 199 are uninitialized\n\nI am not certain whether this constitutes a real security problem in\npractice: the test was conducted in a controlled KMSAN environment and\nthe leaked stack bytes may or may not carry sensitive data on actual\nproduction kernels.  I am reporting it because KMSAN flagged it as a\nkernel-infoleak and the fix is straightforward.  I can provide a\nuserspace reproducer on request.\n\nThe original code used strncpy() which zero-pads to the destination size.\nCommit b04202d6065c (\"net/sched: replace strncpy with strscpy\") replaced\nit with strscpy(), which does not pad, creating this condition.\nZero-initialising the struct closes it.","Type":"Description","Title":"net/sched: fix potential stack infoleak in em_text_dump()"}]}}}