CVE-2026-74307

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-74307", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.883Z", "datePublished": "2026-08-15T05:58:07.969Z", "dateUpdated": "2026-10-30T12:29:40.141Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:29:40.141Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: validate donor file superblock early in EXT4_IOC_MOVE_EXT\n\nReject the EXT4_IOC_MOVE_EXT ioctl early if the donor file does not\nbelong to the same superblock as the original file. Currently, this\nvalidation is performed inside ext4_move_extents() by\nmext_check_validity(), but only after lock_two_nondirectories() has\nalready acquired the inode locks. When the donor fd refers to a file\non a different filesystem (e.g., overlayfs), this late validation\ncreates a circular lock dependency:\n\n CPU0 (overlayfs write) CPU1 (ext4 ioctl)\n ---- ----\n inode_lock(ovl_inode)\n mnt_want_write_file(filp)\n sb_start_write(ext4_sb) [sb_writers]\n backing_file_write_iter()\n vfs_iter_write(real_file)\n file_start_write(real_file)\n sb_start_write(ext4_sb) [blocked by freeze]\n lock_two_nondirectories()\n inode_lock(ovl_inode) [blocked]\n\nWith a concurrent freeze operation holding sb_writers write side, this\nforms a deadlock cycle: CPU0 waits for freeze to complete, freeze waits\nfor CPU1's sb_writers reader to exit, CPU1 waits for CPU0's inode lock.\n\nSince EXT4_IOC_MOVE_EXT exchanges physical extents between two files,\nit fundamentally requires both files to reside on the same ext4\nfilesystem. Moving the superblock check before any lock acquisition\nis both semantically correct and eliminates the circular dependency\nby ensuring that cross-filesystem donor fds are rejected before\nsb_writers or inode locks are taken."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/ext4/ioctl.c"], "versions": [{"version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "lessThan": "23380fc1bf5d3b75dcbd51eb72be4eb0a3300370", "status": "affected", "versionType": "git"}, {"version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "lessThan": "663f184b51492093d408e518efc95ee13b5b4440", "status": "affected", "versionType": "git"}, {"version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "lessThan": "74796e886ca39fcb0d3fd36ea6a39c62784ab6fb", "status": "affected", "versionType": "git"}, {"version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "lessThan": "29e07ec352f0ad06c833a18bf47d82c81f55544f", "status": "affected", "versionType": "git"}, {"version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "lessThan": "fb52013cad9e9b7d3a6a14ea1bcd841e41da7c6c", "status": "affected", "versionType": "git"}, {"version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "lessThan": "c143957520c6c9b5cd72e0de8b52b814f0c576fe", "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/ext4/ioctl.c"], "versions": [{"version": "3.18", "status": "affected"}, {"version": "0", "lessThan": "3.18", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "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": "3.18", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.18", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.18", "versionEndExcluding": "6.12.97"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.18", "versionEndExcluding": "6.18.57"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.18", "versionEndExcluding": "7.1.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.18", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/23380fc1bf5d3b75dcbd51eb72be4eb0a3300370"}, {"url": "https://git.kernel.org/stable/c/663f184b51492093d408e518efc95ee13b5b4440"}, {"url": "https://git.kernel.org/stable/c/74796e886ca39fcb0d3fd36ea6a39c62784ab6fb"}, {"url": "https://git.kernel.org/stable/c/29e07ec352f0ad06c833a18bf47d82c81f55544f"}, {"url": "https://git.kernel.org/stable/c/fb52013cad9e9b7d3a6a14ea1bcd841e41da7c6c"}, {"url": "https://git.kernel.org/stable/c/c143957520c6c9b5cd72e0de8b52b814f0c576fe"}], "title": "ext4: validate donor file superblock early in EXT4_IOC_MOVE_EXT", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/ext4/ioctl.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "23380fc1bf5d3b75dcbd51eb72be4eb0a3300370", "status": "affected", "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "versionType": "git"}, {"lessThan": "663f184b51492093d408e518efc95ee13b5b4440", "status": "affected", "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "versionType": "git"}, {"lessThan": "74796e886ca39fcb0d3fd36ea6a39c62784ab6fb", "status": "affected", "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "versionType": "git"}, {"lessThan": "29e07ec352f0ad06c833a18bf47d82c81f55544f", "status": "affected", "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "versionType": "git"}, {"lessThan": "fb52013cad9e9b7d3a6a14ea1bcd841e41da7c6c", "status": "affected", "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "versionType": "git"}, {"lessThan": "c143957520c6c9b5cd72e0de8b52b814f0c576fe", "status": "affected", "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/ext4/ioctl.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "3.18"}, {"lessThan": "3.18", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.97", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.57", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "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\next4: validate donor file superblock early in EXT4_IOC_MOVE_EXT\n\nReject the EXT4_IOC_MOVE_EXT ioctl early if the donor file does not\nbelong to the same superblock as the original file. Currently, this\nvalidation is performed inside ext4_move_extents() by\nmext_check_validity(), but only after lock_two_nondirectories() has\nalready acquired the inode locks. When the donor fd refers to a file\non a different filesystem (e.g., overlayfs), this late validation\ncreates a circular lock dependency:\n\n CPU0 (overlayfs write) CPU1 (ext4 ioctl)\n ---- ----\n inode_lock(ovl_inode)\n mnt_want_write_file(filp)\n sb_start_write(ext4_sb) [sb_writers]\n backing_file_write_iter()\n vfs_iter_write(real_file)\n file_start_write(real_file)\n sb_start_write(ext4_sb) [blocked by freeze]\n lock_two_nondirectories()\n inode_lock(ovl_inode) [blocked]\n\nWith a concurrent freeze operation holding sb_writers write side, this\nforms a deadlock cycle: CPU0 waits for freeze to complete, freeze waits\nfor CPU1's sb_writers reader to exit, CPU1 waits for CPU0's inode lock.\n\nSince EXT4_IOC_MOVE_EXT exchanges physical extents between two files,\nit fundamentally requires both files to reside on the same ext4\nfilesystem. Moving the superblock check before any lock acquisition\nis both semantically correct and eliminates the circular dependency\nby ensuring that cross-filesystem donor fds are rejected before\nsb_writers or inode locks are taken."}], "id": "CVE-2026-74307", "lastModified": "2026-10-30T13:19:54.650", "metrics": {}, "published": "2026-08-15T06:22:30.500", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/23380fc1bf5d3b75dcbd51eb72be4eb0a3300370"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/29e07ec352f0ad06c833a18bf47d82c81f55544f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/663f184b51492093d408e518efc95ee13b5b4440"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/74796e886ca39fcb0d3fd36ea6a39c62784ab6fb"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c143957520c6c9b5cd72e0de8b52b814f0c576fe"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fb52013cad9e9b7d3a6a14ea1bcd841e41da7c6c"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: ext4: validate donor file superblock early in EXT4_IOC_MOVE_EXT", "id": "2516870", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2516870"}, "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-833", "details": ["In the Linux kernel, the following vulnerability has been resolved:\next4: validate donor file superblock early in EXT4_IOC_MOVE_EXT\nReject the EXT4_IOC_MOVE_EXT ioctl early if the donor file does not\nbelong to the same superblock as the original file. Currently, this\nvalidation is performed inside ext4_move_extents() by\nmext_check_validity(), but only after lock_two_nondirectories() has\nalready acquired the inode locks. When the donor fd refers to a file\non a different filesystem (e.g., overlayfs), this late validation\ncreates a circular lock dependency:\nCPU0 (overlayfs write) CPU1 (ext4 ioctl)\n---- ----\ninode_lock(ovl_inode)\nmnt_want_write_file(filp)\nsb_start_write(ext4_sb) [sb_writers]\nbacking_file_write_iter()\nvfs_iter_write(real_file)\nfile_start_write(real_file)\nsb_start_write(ext4_sb) [blocked by freeze]\nlock_two_nondirectories()\ninode_lock(ovl_inode) [blocked]\nWith a concurrent freeze operation holding sb_writers write side, this\nforms a deadlock cycle: CPU0 waits for freeze to complete, freeze waits\nfor CPU1's sb_writers reader to exit, CPU1 waits for CPU0's inode lock.\nSince EXT4_IOC_MOVE_EXT exchanges physical extents between two files,\nit fundamentally requires both files to reside on the same ext4\nfilesystem. Moving the superblock check before any lock acquisition\nis both semantically correct and eliminates the circular dependency\nby ensuring that cross-filesystem donor fds are rejected before\nsb_writers or inode locks are taken.", "A flaw was found in the Linux kernel's ext4 filesystem. A local attacker can trigger a deadlock by performing an EXT4_IOC_MOVE_EXT ioctl operation with a donor file from a different filesystem during a concurrent freeze operation. This late validation creates a circular lock dependency, leading to a Denial of Service (DoS)."], "name": "CVE-2026-74307", "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": "Out of support scope", "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"}], "public_date": "2026-08-15T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-74307\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-74307\nhttps://lore.kernel.org/linux-cve-announce/2026081551-CVE-2026-74307-8ec9@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a,74796e886ca39fcb0d3fd36ea6a39c62784ab6fb)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a,fb52013cad9e9b7d3a6a14ea1bcd841e41da7c6c)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a,c143957520c6c9b5cd72e0de8b52b814f0c576fe)"}}], "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": "3.18"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,3.18)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.97,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.5,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc1,*)"}}], "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": "2026-08-15T17:00:12.632786+00:00", "updated": "2026-08-22T02:45:03.716811+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}