CVE-2026-98975

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98975", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.383Z", "datePublished": "2026-10-23T12:19:48.379Z", "dateUpdated": "2026-10-24T14:09:45.210Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:09:45.210Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: stop exchanging reflink flags when exchanging mappings\n\nWhen an exchange covers both files from offset 0 to i_disk_size,\nxmi_can_exchange_reflink_flags() assumes every mapping moved and hands\nthe reflink flag over to the other file.\n\nThat assumption is wrong. A file can still own shared blocks past\ni_disk_size, e.g. after EXCHANGE_RANGE_TO_EOF sets a smaller size\nwithout unmapping anything. The flag is cleared anyway, and the next\nwrite to such a block happens in place instead of CoW, corrupting the\nother file that shares it.\n\nCommit a23eca88448e (\"xfs: fix exchange-range reflink flag clearing\nissue with INO1_WRITTEN\") fixed one instance of this. Rather than add\nanother special case, stop moving the flags.\nxfs_exchmaps_ensure_reflink() already sets the flag on both inodes\nbefore the exchange, so both just keep it.\n\nNothing sets CLEAR_INO{1,2}_REFLINK anymore. Intents logged by older\nkernels may still carry them; recovery already masks them off, so they\nstay in the log format mask and are ignored.\n\nXFS_IOC_SWAPEXT has the same problem: it moves the reflink flag from\none inode to the other along with the extents. Just removing that is\nnot enough here: the exchange path flags both inodes up front in\nxfs_exchmaps_ensure_reflink(), but swapext has no such step, so the\ninode receiving the shared extents would be left without the flag.\nSet it on both inodes instead, and make sure both have a CoW fork,\nsince an inode with the reflink flag is expected to have one.\n\nThe flag now stays until FALLOC_FL_UNSHARE_RANGE, xfs_scrub, or a\ntruncate to zero removes it."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - `ioctl(2)` runs `do_vfs_ioctl()`/`vfs_ioctl()` \u2192 `xfs_file_ioctl()` \u2192 `xfs_ioc_exchange_range()` \u2192 `xfs_exchange_mappings()` \u2192 patched `xfs_exchmaps_init_intent()`; all causal file descriptors, offsets, and flags are supplied locally.\nAC:L - On a reflink/exchange-range XFS, the attacker can clone a target block, use chosen `TO_EOF` offsets to strand it past `i_disk_size`, perform a full-range exchange so `xmi_can_exchange_reflink_flags()` clears the flag, and `pwrite` the shared block; no race or external event is required.\nPR:L - `xfs_exchange_range()` requires only read-write scratch-file descriptors and `remap_verify_area(..., true)`, with no `capable()` check; FICLONE requires only read access to the protected source and write access to an attacker-owned destination.\nUI:N - The attacker personally performs FICLONERANGE, the crafted `XFS_IOC_EXCHANGE_RANGE` operations, and the final `pwrite`; no victim must mount media, open a file, or take another action.\nS:U - `xfs_exchmaps_clear_reflink()` breaks CoW isolation between inodes on the same XFS host; using the resulting protected-file overwrite for root access is a standard local privilege escalation, not a VM, IOMMU, or other security-authority escape.\nC:H - The attacker can clone a readable SUID-root binary, then make the faulty non-CoW write alter its physical block without modifying its inode or clearing SUID metadata; executing the corrupted binary can yield root and unrestricted access to host-confidential data.\nI:H - After `xfs_exchmaps_clear_reflink()` removes the flag, `xfs_is_cow_inode()` is false and the iomap write path updates the still-shared block in place, permitting persistent attacker-controlled modification of readable protected files without write permission.\nA:H - The same in-place primitive can corrupt readable boot-critical executables, and overwriting a SUID-root binary can provide root control capable of stopping the host, supporting complete availability loss."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/xfs/libxfs/xfs_exchmaps.c", "fs/xfs/libxfs/xfs_log_format.h", "fs/xfs/xfs_bmap_util.c"], "versions": [{"version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "lessThan": "1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be", "status": "affected", "versionType": "git"}, {"version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "lessThan": "7d3b9b2c9dc57f93f36c716ab752548cb4db9900", "status": "affected", "versionType": "git"}, {"version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "lessThan": "4756c94260e69ce42612b8220c3614f02f7a11d5", "status": "affected", "versionType": "git"}, {"version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "lessThan": "d84d6c1a7f1e2de9e601703a326a4c1b7b421943", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/xfs/libxfs/xfs_exchmaps.c", "fs/xfs/libxfs/xfs_log_format.h", "fs/xfs/xfs_bmap_util.c"], "versions": [{"version": "4.9", "status": "affected"}, {"version": "0", "lessThan": "4.9", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.11", "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": "4.9", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.9", "versionEndExcluding": "6.18.57"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.9", "versionEndExcluding": "7.2.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.9", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be"}, {"url": "https://git.kernel.org/stable/c/7d3b9b2c9dc57f93f36c716ab752548cb4db9900"}, {"url": "https://git.kernel.org/stable/c/4756c94260e69ce42612b8220c3614f02f7a11d5"}, {"url": "https://git.kernel.org/stable/c/d84d6c1a7f1e2de9e601703a326a4c1b7b421943"}], "title": "xfs: stop exchanging reflink flags when exchanging mappings", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/xfs/libxfs/xfs_exchmaps.c", "fs/xfs/libxfs/xfs_log_format.h", "fs/xfs/xfs_bmap_util.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be", "status": "affected", "version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "versionType": "git"}, {"lessThan": "7d3b9b2c9dc57f93f36c716ab752548cb4db9900", "status": "affected", "version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "versionType": "git"}, {"lessThan": "4756c94260e69ce42612b8220c3614f02f7a11d5", "status": "affected", "version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "versionType": "git"}, {"lessThan": "d84d6c1a7f1e2de9e601703a326a4c1b7b421943", "status": "affected", "version": "f0bc4d134b46607967bda1205ce3226a1bd95f42", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/xfs/libxfs/xfs_exchmaps.c", "fs/xfs/libxfs/xfs_log_format.h", "fs/xfs/xfs_bmap_util.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "4.9"}, {"lessThan": "4.9", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.114", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.57", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: stop exchanging reflink flags when exchanging mappings\n\nWhen an exchange covers both files from offset 0 to i_disk_size,\nxmi_can_exchange_reflink_flags() assumes every mapping moved and hands\nthe reflink flag over to the other file.\n\nThat assumption is wrong. A file can still own shared blocks past\ni_disk_size, e.g. after EXCHANGE_RANGE_TO_EOF sets a smaller size\nwithout unmapping anything. The flag is cleared anyway, and the next\nwrite to such a block happens in place instead of CoW, corrupting the\nother file that shares it.\n\nCommit a23eca88448e (\"xfs: fix exchange-range reflink flag clearing\nissue with INO1_WRITTEN\") fixed one instance of this. Rather than add\nanother special case, stop moving the flags.\nxfs_exchmaps_ensure_reflink() already sets the flag on both inodes\nbefore the exchange, so both just keep it.\n\nNothing sets CLEAR_INO{1,2}_REFLINK anymore. Intents logged by older\nkernels may still carry them; recovery already masks them off, so they\nstay in the log format mask and are ignored.\n\nXFS_IOC_SWAPEXT has the same problem: it moves the reflink flag from\none inode to the other along with the extents. Just removing that is\nnot enough here: the exchange path flags both inodes up front in\nxfs_exchmaps_ensure_reflink(), but swapext has no such step, so the\ninode receiving the shared extents would be left without the flag.\nSet it on both inodes instead, and make sure both have a CoW fork,\nsince an inode with the reflink flag is expected to have one.\n\nThe flag now stays until FALLOC_FL_UNSHARE_RANGE, xfs_scrub, or a\ntruncate to zero removes it."}], "id": "CVE-2026-98975", "lastModified": "2026-10-24T14:16:50.093", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-10-23T13:17:19.157", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4756c94260e69ce42612b8220c3614f02f7a11d5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7d3b9b2c9dc57f93f36c716ab752548cb4db9900"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d84d6c1a7f1e2de9e601703a326a4c1b7b421943"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: xfs: stop exchanging reflink flags when exchanging mappings", "id": "2559805", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2559805"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N", "status": "draft"}, "cwe": "CWE-1025", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nxfs: stop exchanging reflink flags when exchanging mappings\nWhen an exchange covers both files from offset 0 to i_disk_size,\nxmi_can_exchange_reflink_flags() assumes every mapping moved and hands\nthe reflink flag over to the other file.\nThat assumption is wrong. A file can still own shared blocks past\ni_disk_size, e.g. after EXCHANGE_RANGE_TO_EOF sets a smaller size\nwithout unmapping anything. The flag is cleared anyway, and the next\nwrite to such a block happens in place instead of CoW, corrupting the\nother file that shares it.\nCommit a23eca88448e (\"xfs: fix exchange-range reflink flag clearing\nissue with INO1_WRITTEN\") fixed one instance of this. Rather than add\nanother special case, stop moving the flags.\nxfs_exchmaps_ensure_reflink() already sets the flag on both inodes\nbefore the exchange, so both just keep it.\nNothing sets CLEAR_INO{1,2}_REFLINK anymore. Intents logged by older\nkernels may still carry them; recovery already masks them off, so they\nstay in the log format mask and are ignored.\nXFS_IOC_SWAPEXT has the same problem: it moves the reflink flag from\none inode to the other along with the extents. Just removing that is\nnot enough here: the exchange path flags both inodes up front in\nxfs_exchmaps_ensure_reflink(), but swapext has no such step, so the\ninode receiving the shared extents would be left without the flag.\nSet it on both inodes instead, and make sure both have a CoW fork,\nsince an inode with the reflink flag is expected to have one.\nThe flag now stays until FALLOC_FL_UNSHARE_RANGE, xfs_scrub, or a\ntruncate to zero removes it.", "A flaw was found in the Linux kernel's XFS file system. A local user could exploit this flaw to cause data corruption across shared files during file exchange operations. When exchanging file storage mappings, the kernel may improperly clear the reference link (reflink) flag that marks blocks as shared. As a result, subsequent writes modify the shared blocks directly in place instead of creating a new copy through Copy-on-Write (CoW), inadvertently corrupting other files sharing those blocks."], "name": "CVE-2026-98975", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-23T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98975\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98975\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98975.mbox"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,7d3b9b2c9dc57f93f36c716ab752548cb4db9900)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,4756c94260e69ce42612b8220c3614f02f7a11d5)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,d84d6c1a7f1e2de9e601703a326a4c1b7b421943)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "4.9"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,4.9)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.114,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.57,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.11,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,7d3b9b2c9dc57f93f36c716ab752548cb4db9900)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,4756c94260e69ce42612b8220c3614f02f7a11d5)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f0bc4d134b46607967bda1205ce3226a1bd95f42,d84d6c1a7f1e2de9e601703a326a4c1b7b421943)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "4.9"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,4.9)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.114,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.57,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.11,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-10-23T15:00:13.040649+00:00", "updated": "2026-10-29T14:30:16.101579+00:00", "vendors": ["linux", "linux$PRODUCT$linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-665", "CWE-1025"]}