{"api_version":"1","generated_at":"2026-09-25T12:39:46+00:00","cve":"CVE-2026-98124","urls":{"html":"https://cve.report/CVE-2026-98124","api":"https://cve.report/api/cve/CVE-2026-98124.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98124","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98124"},"summary":{"title":"smb/client: invalidate fscache for fallocate range operations","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: invalidate fscache for fallocate range operations\n\nsmb3_zero_range(), smb3_punch_hole(), smb3_insert_range(), and\nsmb3_collapse_range() modify file contents through server-side range\noperations. These operations discard the affected page cache, but leave\nthe FS-Cache cookie valid, so a later read may return data cached before\nthe range operation.\n\nFix this by invalidating FS-Cache after outstanding I/O has completed\nand before modifying the file on the server.\n\nRun the following as root on a CIFS mount with fsc enabled and an active\nCacheFiles backend:\n\n        bash -c '\n                MNT=/mnt/cifs\n                FILE=\"$MNT/repro\"\n\n                # Generate four 1 MiB random blocks: [A][B][C][D].\n                dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none\n\n                # Expected contents after zeroing B: [A][zero][C][D].\n                cp /tmp/src /tmp/expected\n                dd if=/dev/zero of=/tmp/expected bs=1M seek=1 count=1 \\\n                        conv=notrunc status=none\n                cp /tmp/src \"$FILE\"\n\n                # Populate FS-Cache, then discard the page cache.\n                sync\n                echo 1 > /proc/sys/vm/drop_caches\n                cat \"$FILE\" > /dev/null\n                sync\n                echo 1 > /proc/sys/vm/drop_caches\n\n                fallocate --zero-range -o 1M -l 1M \"$FILE\"\n\n                if cmp -s /tmp/expected \"$FILE\"; then\n                        echo \"readback: OK\"\n                else\n                        echo \"readback: STALE DATA\"\n                fi\n        '\n\nBefore this change, the readback differs from /tmp/expected:\n\n        readback: STALE DATA\n\nAfter this change, it matches:\n\n        readback: OK","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-25 11:17:43","updated_at":"2026-09-25 11:17:43"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/93c6e5a8d7c5071d586c1411596d5db5faad22b2","name":"https://git.kernel.org/stable/c/93c6e5a8d7c5071d586c1411596d5db5faad22b2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/448ba0ae65ca61064183564d2983c9aa59bd6ba7","name":"https://git.kernel.org/stable/c/448ba0ae65ca61064183564d2983c9aa59bd6ba7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98124","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98124","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 31742c5a331766bc7df6b0d525df00c6cd20d5a6 93c6e5a8d7c5071d586c1411596d5db5faad22b2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 31742c5a331766bc7df6b0d525df00c6cd20d5a6 448ba0ae65ca61064183564d2983c9aa59bd6ba7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3.17","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 3.17 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-rc2 * 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":["fs/smb/client/smb2ops.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"93c6e5a8d7c5071d586c1411596d5db5faad22b2","status":"affected","version":"31742c5a331766bc7df6b0d525df00c6cd20d5a6","versionType":"git"},{"lessThan":"448ba0ae65ca61064183564d2983c9aa59bd6ba7","status":"affected","version":"31742c5a331766bc7df6b0d525df00c6cd20d5a6","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/smb/client/smb2ops.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"3.17"},{"lessThan":"3.17","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"3.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc2","versionStartIncluding":"3.17","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: invalidate fscache for fallocate range operations\n\nsmb3_zero_range(), smb3_punch_hole(), smb3_insert_range(), and\nsmb3_collapse_range() modify file contents through server-side range\noperations. These operations discard the affected page cache, but leave\nthe FS-Cache cookie valid, so a later read may return data cached before\nthe range operation.\n\nFix this by invalidating FS-Cache after outstanding I/O has completed\nand before modifying the file on the server.\n\nRun the following as root on a CIFS mount with fsc enabled and an active\nCacheFiles backend:\n\n        bash -c '\n                MNT=/mnt/cifs\n                FILE=\"$MNT/repro\"\n\n                # Generate four 1 MiB random blocks: [A][B][C][D].\n                dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none\n\n                # Expected contents after zeroing B: [A][zero][C][D].\n                cp /tmp/src /tmp/expected\n                dd if=/dev/zero of=/tmp/expected bs=1M seek=1 count=1 \\\n                        conv=notrunc status=none\n                cp /tmp/src \"$FILE\"\n\n                # Populate FS-Cache, then discard the page cache.\n                sync\n                echo 1 > /proc/sys/vm/drop_caches\n                cat \"$FILE\" > /dev/null\n                sync\n                echo 1 > /proc/sys/vm/drop_caches\n\n                fallocate --zero-range -o 1M -l 1M \"$FILE\"\n\n                if cmp -s /tmp/expected \"$FILE\"; then\n                        echo \"readback: OK\"\n                else\n                        echo \"readback: STALE DATA\"\n                fi\n        '\n\nBefore this change, the readback differs from /tmp/expected:\n\n        readback: STALE DATA\n\nAfter this change, it matches:\n\n        readback: OK"}],"providerMetadata":{"dateUpdated":"2026-09-25T10:36:06.581Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/93c6e5a8d7c5071d586c1411596d5db5faad22b2"},{"url":"https://git.kernel.org/stable/c/448ba0ae65ca61064183564d2983c9aa59bd6ba7"}],"title":"smb/client: invalidate fscache for fallocate range operations","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98124","datePublished":"2026-09-25T10:36:06.581Z","dateReserved":"2026-09-25T10:25:14.318Z","dateUpdated":"2026-09-25T10:36:06.581Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-25 11:17:43","lastModifiedDate":"2026-09-25 11:17:43","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98124","Ordinal":"1","Title":"smb/client: invalidate fscache for fallocate range operations","CVE":"CVE-2026-98124","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98124","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: invalidate fscache for fallocate range operations\n\nsmb3_zero_range(), smb3_punch_hole(), smb3_insert_range(), and\nsmb3_collapse_range() modify file contents through server-side range\noperations. These operations discard the affected page cache, but leave\nthe FS-Cache cookie valid, so a later read may return data cached before\nthe range operation.\n\nFix this by invalidating FS-Cache after outstanding I/O has completed\nand before modifying the file on the server.\n\nRun the following as root on a CIFS mount with fsc enabled and an active\nCacheFiles backend:\n\n        bash -c '\n                MNT=/mnt/cifs\n                FILE=\"$MNT/repro\"\n\n                # Generate four 1 MiB random blocks: [A][B][C][D].\n                dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none\n\n                # Expected contents after zeroing B: [A][zero][C][D].\n                cp /tmp/src /tmp/expected\n                dd if=/dev/zero of=/tmp/expected bs=1M seek=1 count=1 \\\n                        conv=notrunc status=none\n                cp /tmp/src \"$FILE\"\n\n                # Populate FS-Cache, then discard the page cache.\n                sync\n                echo 1 > /proc/sys/vm/drop_caches\n                cat \"$FILE\" > /dev/null\n                sync\n                echo 1 > /proc/sys/vm/drop_caches\n\n                fallocate --zero-range -o 1M -l 1M \"$FILE\"\n\n                if cmp -s /tmp/expected \"$FILE\"; then\n                        echo \"readback: OK\"\n                else\n                        echo \"readback: STALE DATA\"\n                fi\n        '\n\nBefore this change, the readback differs from /tmp/expected:\n\n        readback: STALE DATA\n\nAfter this change, it matches:\n\n        readback: OK","Type":"Description","Title":"smb/client: invalidate fscache for fallocate range operations"}]}}}