CVE-2026-98067

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98067", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:19:56.074Z", "datePublished": "2026-09-25T10:24:09.610Z", "dateUpdated": "2026-10-21T12:54:21.582Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:54:21.582Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: disable LZ4 rolling decompression for now\n\nLZ4 rolling decompression [1] was introduced to reduce the memory\nfootprint of temporary pages:\n\n For many cases, it is needed for users to read small data within\n a compressed extent (pcluster), either due to random small read, or\n since uptodate folios (typically order-0) cannot be reused for\n decompression again since decompression algorithm refills\n already-uptodate folios.\n\nRolling decompression works because LZ4 is LZ77-based and only refers\nto the most recent 64 KiB of decompressed data, so in theory only a\nbounded rolling window of temporary pages is needed when decompressing.\n\nIt can save a lot of temporary memory, e.g.\n 601,960-byte data can be compressed into a 256k LZ4 compressed extent,\n which means it needs 146 extra pages per request in the worst case if\n rolling decompression is disabled.\n\nHowever, the upstream LZ4 implementation is not under EROFS' control:\nFor example, the literal copy memmove() may still **copy long literals\nbackward** on x86 based on the address comparison even when the source\nand destination ranges do not overlap (IOWs, inline decompression\ndoesn't need to be considered here). That breaks the rolling assumption\nand makes the optimization broken.\n\nDisable it for now to make sure the data correctness first since EROFS\nis used everywhere now: The rolling window approach can be revived once\nwe either ensure that the official LZ4 code always copies forward for\nnon-overlapping ranges or maintain our own LZ4 implementation in EROFS.\n\nThe main impact is a higher runtime memory footprint; However, recent\ncommit 0f6273ab4637 (\"erofs: add a reserved buffer pool for lz4\ndecompression\") helps mitigate this when enabled but it's still not\nperfect.\n\n[1] https://www.usenix.org/conference/atc19/presentation/gao\n \u00a7 3.3 Decompression"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/erofs/decompressor.c", "fs/erofs/internal.h", "fs/erofs/zdata.c"], "versions": [{"version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "lessThan": "dcc5e6c9e4d06fe73fc61e730ee3e51dd115a4d8", "status": "affected", "versionType": "git"}, {"version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "lessThan": "d923e53472b468a50a6cf41341531d5170c68371", "status": "affected", "versionType": "git"}, {"version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "lessThan": "ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2", "status": "affected", "versionType": "git"}, {"version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "lessThan": "c9a2db4b9950b59c571258e4bae74c271f62dd66", "status": "affected", "versionType": "git"}, {"version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "lessThan": "82e664cf1219c459c33aae931b222cf951af9cb7", "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/erofs/decompressor.c", "fs/erofs/internal.h", "fs/erofs/zdata.c"], "versions": [{"version": "5.13", "status": "affected"}, {"version": "0", "lessThan": "5.13", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.7", "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": "5.13", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "6.18.53"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "7.2.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/dcc5e6c9e4d06fe73fc61e730ee3e51dd115a4d8"}, {"url": "https://git.kernel.org/stable/c/d923e53472b468a50a6cf41341531d5170c68371"}, {"url": "https://git.kernel.org/stable/c/ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2"}, {"url": "https://git.kernel.org/stable/c/c9a2db4b9950b59c571258e4bae74c271f62dd66"}, {"url": "https://git.kernel.org/stable/c/82e664cf1219c459c33aae931b222cf951af9cb7"}], "title": "erofs: disable LZ4 rolling decompression for now", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/erofs/decompressor.c", "fs/erofs/internal.h", "fs/erofs/zdata.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "dcc5e6c9e4d06fe73fc61e730ee3e51dd115a4d8", "status": "affected", "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "versionType": "git"}, {"lessThan": "d923e53472b468a50a6cf41341531d5170c68371", "status": "affected", "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "versionType": "git"}, {"lessThan": "ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2", "status": "affected", "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "versionType": "git"}, {"lessThan": "c9a2db4b9950b59c571258e4bae74c271f62dd66", "status": "affected", "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "versionType": "git"}, {"lessThan": "82e664cf1219c459c33aae931b222cf951af9cb7", "status": "affected", "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/erofs/decompressor.c", "fs/erofs/internal.h", "fs/erofs/zdata.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.13"}, {"lessThan": "5.13", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.114", "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"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: disable LZ4 rolling decompression for now\n\nLZ4 rolling decompression [1] was introduced to reduce the memory\nfootprint of temporary pages:\n\n For many cases, it is needed for users to read small data within\n a compressed extent (pcluster), either due to random small read, or\n since uptodate folios (typically order-0) cannot be reused for\n decompression again since decompression algorithm refills\n already-uptodate folios.\n\nRolling decompression works because LZ4 is LZ77-based and only refers\nto the most recent 64 KiB of decompressed data, so in theory only a\nbounded rolling window of temporary pages is needed when decompressing.\n\nIt can save a lot of temporary memory, e.g.\n 601,960-byte data can be compressed into a 256k LZ4 compressed extent,\n which means it needs 146 extra pages per request in the worst case if\n rolling decompression is disabled.\n\nHowever, the upstream LZ4 implementation is not under EROFS' control:\nFor example, the literal copy memmove() may still **copy long literals\nbackward** on x86 based on the address comparison even when the source\nand destination ranges do not overlap (IOWs, inline decompression\ndoesn't need to be considered here). That breaks the rolling assumption\nand makes the optimization broken.\n\nDisable it for now to make sure the data correctness first since EROFS\nis used everywhere now: The rolling window approach can be revived once\nwe either ensure that the official LZ4 code always copies forward for\nnon-overlapping ranges or maintain our own LZ4 implementation in EROFS.\n\nThe main impact is a higher runtime memory footprint; However, recent\ncommit 0f6273ab4637 (\"erofs: add a reserved buffer pool for lz4\ndecompression\") helps mitigate this when enabled but it's still not\nperfect.\n\n[1] https://www.usenix.org/conference/atc19/presentation/gao\n \u00a7 3.3 Decompression"}], "id": "CVE-2026-98067", "lastModified": "2026-10-21T13:21:21.163", "metrics": {}, "published": "2026-09-25T11:17:35.787", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/82e664cf1219c459c33aae931b222cf951af9cb7"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c9a2db4b9950b59c571258e4bae74c271f62dd66"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d923e53472b468a50a6cf41341531d5170c68371"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/dcc5e6c9e4d06fe73fc61e730ee3e51dd115a4d8"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Undergoing Analysis"}

{"bugzilla": {"description": "kernel: erofs: disable LZ4 rolling decompression for now", "id": "2541261", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2541261"}, "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:N/A:H", "status": "draft"}, "cwe": "CWE-440", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nerofs: disable LZ4 rolling decompression for now\nLZ4 rolling decompression [1] was introduced to reduce the memory\nfootprint of temporary pages:\nFor many cases, it is needed for users to read small data within\na compressed extent (pcluster), either due to random small read, or\nsince uptodate folios (typically order-0) cannot be reused for\ndecompression again since decompression algorithm refills\nalready-uptodate folios.\nRolling decompression works because LZ4 is LZ77-based and only refers\nto the most recent 64 KiB of decompressed data, so in theory only a\nbounded rolling window of temporary pages is needed when decompressing.\nIt can save a lot of temporary memory, e.g.\n601,960-byte data can be compressed into a 256k LZ4 compressed extent,\nwhich means it needs 146 extra pages per request in the worst case if\nrolling decompression is disabled.\nHowever, the upstream LZ4 implementation is not under EROFS' control:\nFor example, the literal copy memmove() may still **copy long literals\nbackward** on x86 based on the address comparison even when the source\nand destination ranges do not overlap (IOWs, inline decompression\ndoesn't need to be considered here). That breaks the rolling assumption\nand makes the optimization broken.\nDisable it for now to make sure the data correctness first since EROFS\nis used everywhere now: The rolling window approach can be revived once\nwe either ensure that the official LZ4 code always copies forward for\nnon-overlapping ranges or maintain our own LZ4 implementation in EROFS.\nThe main impact is a higher runtime memory footprint; However, recent\ncommit 0f6273ab4637 (\"erofs: add a reserved buffer pool for lz4\ndecompression\") helps mitigate this when enabled but it's still not\nperfect.\n[1] https://www.usenix.org/conference/atc19/presentation/gao\n\u00a7 3.3 Decompression", "A flaw was found in the Linux kernel's EROFS (Enhanced Read-Only File System). The rolling decompression mechanism used for LZ4-compressed files assumes that data is always copied forward in memory. On certain system architectures, the underlying memory copy operation can copy backward, invalidating the rolling buffer and corrupting the decompressed output. A local user reading compressed data from an EROFS file system can trigger this flaw, leading to data corruption and the retrieval of incorrect information."], "name": "CVE-2026-98067", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-09-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98067\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98067\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98067.mbox"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[8e6c8fa9f2e95c88a642521a5da19a8e31748846,ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[8e6c8fa9f2e95c88a642521a5da19a8e31748846,c9a2db4b9950b59c571258e4bae74c271f62dd66)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[8e6c8fa9f2e95c88a642521a5da19a8e31748846,82e664cf1219c459c33aae931b222cf951af9cb7)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"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": "5.13"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.13)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.53,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.7,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc3,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-25T15:45:19.068710+00:00", "updated": "2026-09-30T15:15:16.180420+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}