{"api_version":"1","generated_at":"2026-10-27T04:24:48+00:00","cve":"CVE-2026-98400","urls":{"html":"https://cve.report/CVE-2026-98400","api":"https://cve.report/api/cve/CVE-2026-98400.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98400","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98400"},"summary":{"title":"s390/ipl: Fix NULL deref in kdump without re-IPL parm block","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/ipl: Fix NULL deref in kdump without re-IPL parm block\n\nSome IPL types, like HMC FTP boot or QEMU direct kernel boot, might\nnot provide an IPL parameter block. In this case, reipl_type_init()\nselects IPL_TYPE_UNKNOWN, and reipl_block_actual remains NULL.\n\nkdump passes the re-IPL parameter block to the dump kernel through\nos_info. Before commit 3b9678472bab (\"s390/ipl: correct kdump reipl\nblock checksum calculation\"), the os_info entry was added only for\nIPL types which initialized reipl_block_actual. That commit moved the\nos_info update to machine_crash_shutdown(), making it unconditional. As\na result, set_os_info_reipl_block() dereferences reipl_block_actual for\nIPL_TYPE_UNKNOWN. This may happen to work by chance when address zero\ncontains readable lowcore data and the resulting empty os_info entry is\nignored by the dump kernel.\n\nSkip the os_info update when no re-IPL parameter block is available.\nKdump then collect the dump and reboot without setting re-IPL parameter\nblock.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-14 14:17:51","updated_at":"2026-10-19 10:18:44"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/7f918871112e8e7c581e99eb8e545af4e59c8367","name":"https://git.kernel.org/stable/c/7f918871112e8e7c581e99eb8e545af4e59c8367","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b6bf82bc5e00afaf836f8bb9a676bffc182a6bbd","name":"https://git.kernel.org/stable/c/b6bf82bc5e00afaf836f8bb9a676bffc182a6bbd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/030e88812435fc5d6aa42eee41fa77b5ea620327","name":"https://git.kernel.org/stable/c/030e88812435fc5d6aa42eee41fa77b5ea620327","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/92d0829eae257544b6b0faccb6e7079c45e22d48","name":"https://git.kernel.org/stable/c/92d0829eae257544b6b0faccb6e7079c45e22d48","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/50f9c40768e84f30d374235b3ee3850a94d9ac29","name":"https://git.kernel.org/stable/c/50f9c40768e84f30d374235b3ee3850a94d9ac29","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98400","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98400","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3b9678472bab86ae654cf2c18d5dd551558045be 030e88812435fc5d6aa42eee41fa77b5ea620327 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3b9678472bab86ae654cf2c18d5dd551558045be 92d0829eae257544b6b0faccb6e7079c45e22d48 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3b9678472bab86ae654cf2c18d5dd551558045be 50f9c40768e84f30d374235b3ee3850a94d9ac29 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3b9678472bab86ae654cf2c18d5dd551558045be b6bf82bc5e00afaf836f8bb9a676bffc182a6bbd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3b9678472bab86ae654cf2c18d5dd551558045be 7f918871112e8e7c581e99eb8e545af4e59c8367 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.17","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.17 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.158 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.111 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.53 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 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":["arch/s390/kernel/ipl.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"030e88812435fc5d6aa42eee41fa77b5ea620327","status":"affected","version":"3b9678472bab86ae654cf2c18d5dd551558045be","versionType":"git"},{"lessThan":"92d0829eae257544b6b0faccb6e7079c45e22d48","status":"affected","version":"3b9678472bab86ae654cf2c18d5dd551558045be","versionType":"git"},{"lessThan":"50f9c40768e84f30d374235b3ee3850a94d9ac29","status":"affected","version":"3b9678472bab86ae654cf2c18d5dd551558045be","versionType":"git"},{"lessThan":"b6bf82bc5e00afaf836f8bb9a676bffc182a6bbd","status":"affected","version":"3b9678472bab86ae654cf2c18d5dd551558045be","versionType":"git"},{"lessThan":"7f918871112e8e7c581e99eb8e545af4e59c8367","status":"affected","version":"3b9678472bab86ae654cf2c18d5dd551558045be","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/s390/kernel/ipl.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.17"},{"lessThan":"4.17","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.158","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.111","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.53","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","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":"6.6.158","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.111","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.53","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"4.17","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/ipl: Fix NULL deref in kdump without re-IPL parm block\n\nSome IPL types, like HMC FTP boot or QEMU direct kernel boot, might\nnot provide an IPL parameter block. In this case, reipl_type_init()\nselects IPL_TYPE_UNKNOWN, and reipl_block_actual remains NULL.\n\nkdump passes the re-IPL parameter block to the dump kernel through\nos_info. Before commit 3b9678472bab (\"s390/ipl: correct kdump reipl\nblock checksum calculation\"), the os_info entry was added only for\nIPL types which initialized reipl_block_actual. That commit moved the\nos_info update to machine_crash_shutdown(), making it unconditional. As\na result, set_os_info_reipl_block() dereferences reipl_block_actual for\nIPL_TYPE_UNKNOWN. This may happen to work by chance when address zero\ncontains readable lowcore data and the resulting empty os_info entry is\nignored by the dump kernel.\n\nSkip the os_info update when no re-IPL parameter block is available.\nKdump then collect the dump and reboot without setting re-IPL parameter\nblock."}],"providerMetadata":{"dateUpdated":"2026-10-19T09:18:53.762Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/030e88812435fc5d6aa42eee41fa77b5ea620327"},{"url":"https://git.kernel.org/stable/c/92d0829eae257544b6b0faccb6e7079c45e22d48"},{"url":"https://git.kernel.org/stable/c/50f9c40768e84f30d374235b3ee3850a94d9ac29"},{"url":"https://git.kernel.org/stable/c/b6bf82bc5e00afaf836f8bb9a676bffc182a6bbd"},{"url":"https://git.kernel.org/stable/c/7f918871112e8e7c581e99eb8e545af4e59c8367"}],"title":"s390/ipl: Fix NULL deref in kdump without re-IPL parm block","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98400","datePublished":"2026-10-14T13:26:00.872Z","dateReserved":"2026-09-25T10:25:14.346Z","dateUpdated":"2026-10-19T09:18:53.762Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-14 14:17:51","lastModifiedDate":"2026-10-19 10:18:44","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98400","Ordinal":"1","Title":"s390/ipl: Fix NULL deref in kdump without re-IPL parm block","CVE":"CVE-2026-98400","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98400","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/ipl: Fix NULL deref in kdump without re-IPL parm block\n\nSome IPL types, like HMC FTP boot or QEMU direct kernel boot, might\nnot provide an IPL parameter block. In this case, reipl_type_init()\nselects IPL_TYPE_UNKNOWN, and reipl_block_actual remains NULL.\n\nkdump passes the re-IPL parameter block to the dump kernel through\nos_info. Before commit 3b9678472bab (\"s390/ipl: correct kdump reipl\nblock checksum calculation\"), the os_info entry was added only for\nIPL types which initialized reipl_block_actual. That commit moved the\nos_info update to machine_crash_shutdown(), making it unconditional. As\na result, set_os_info_reipl_block() dereferences reipl_block_actual for\nIPL_TYPE_UNKNOWN. This may happen to work by chance when address zero\ncontains readable lowcore data and the resulting empty os_info entry is\nignored by the dump kernel.\n\nSkip the os_info update when no re-IPL parameter block is available.\nKdump then collect the dump and reboot without setting re-IPL parameter\nblock.","Type":"Description","Title":"s390/ipl: Fix NULL deref in kdump without re-IPL parm block"}]}}}