{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-93262", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-17T16:02:15.097Z", "datePublished": "2026-09-24T15:52:01.886Z", "dateUpdated": "2026-10-19T09:08:15.484Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:08:15.484Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmd/raid5-ppl: fix use-after-free in ppl_do_flush()\n\nThe loop in ppl_do_flush() continues iterating after calling\nppl_io_unit_finished(), touching io->pending_flushes and leading to a\nuse-after-free.\n\nAdd a break statement to stop the loop once io is freed." } ], "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 - The patched ppl_do_flush() runs from ppl_stripe_write_finished() after RAID5 stripe data+parity I/O completes. Those writes enter via md_submit_bio() -> raid5_make_request() from local write(2) to a filesystem or /dev/md*; ppl_submit_iounit() only sets disk_flush_bitmap from local stripe R5_Wantwrite/wb_cache_on state, not from a network protocol message.\nAC:L - Writes the attacker issues are logged by ppl_write_stripe()/ppl_log_stripe() and ppl_submit_iounit() sets disk_flush_bitmap for child_logs[i].wb_cache_on members. When pending_stripes hits 0, ppl_stripe_write_finished() calls ppl_do_flush(); the remainder loop's missing break after ppl_io_unit_finished() is a logic bug on that path, not a second-actor race or a disk-fault precondition.\nPR:L - md_submit_bio() and raid5_make_request() have no capability check; md_ioctl()'s capable(CAP_SYS_ADMIN) applies only to array-management ioctls, not I/O. An unprivileged user who can write a filesystem on the RAID5+PPL array (or /dev/md* with disk-group write access) reaches ppl_do_flush() without init-namespace root.\nUI:N - The attacker triggers ppl_do_flush() through their own writes: raid5 handle_stripe()/handle_stripe_clean_event() calls ppl_stripe_write_finished() on I/O they submitted. No victim action such as mounting an image or plugging a device is required.\nS:U - ppl_io_unit_finished() mempool_free()s the ppl_io_unit from ppl_conf->io_pool in the host md/raid5 kernel. The later dangling atomic_dec_and_test(&io->pending_flushes) in ppl_do_flush() stays in that kernel's authority and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - ppl_io_unit_finished() returns the ppl_io_unit to io_pool via mempool_free(); ppl_do_flush()'s remainder loop then does atomic_dec_and_test(&io->pending_flushes) on that freed kmem_cache object. A UAF of the recycled io_unit header is a kernel read primitive against adjacent/reconstituted pool memory.\nI:H - The same dangling io is a writeable ppl_io_unit: atomic_dec_and_test() mutates pending_flushes on a recycled object, and another true dec_and_test would call ppl_io_unit_finished() again (list_del/mempool_free of a live unit). That is a kernel write/double-free primitive on the PPL io_unit cache.\nA:H - Use-after-free of the mempool ppl_io_unit in ppl_do_flush() after ppl_io_unit_finished() can oops on the stale pending_flushes access or corrupt list_del() pointers in a second finish, panicking the host." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/md/raid5-ppl.c" ], "versions": [ { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "cf01f9413565e86673baf927291a088b6975692b", "status": "affected", "versionType": "git" }, { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "e7505842f1329ece90cb9ea0db87772aeca44052", "status": "affected", "versionType": "git" }, { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "b5123bf667ac29ddd8106f9ca7cc01316513ae66", "status": "affected", "versionType": "git" }, { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "e77c80670f2c2bf491da9b173931e1da4677c23a", "status": "affected", "versionType": "git" }, { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "8914c3d40870f16429a326e97e4016bedc6ede4c", "status": "affected", "versionType": "git" }, { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "455b56209f9615c3902dcc398dd867abb5ade3ab", "status": "affected", "versionType": "git" }, { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "fcf21df7d3c50c8ebeb0757df5d21b02dcae4218", "status": "affected", "versionType": "git" }, { "version": "1532d9e87e8b2377f12929f9e40724d5fbe6ecc5", "lessThan": "371f7a1b392edc8b7cf449cc7713179b588f2d0e", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/md/raid5-ppl.c" ], "versions": [ { "version": "4.16", "status": "affected" }, { "version": "0", "lessThan": "4.16", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "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": "4.16", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.12.110" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.18.52" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/cf01f9413565e86673baf927291a088b6975692b" }, { "url": "https://git.kernel.org/stable/c/e7505842f1329ece90cb9ea0db87772aeca44052" }, { "url": "https://git.kernel.org/stable/c/b5123bf667ac29ddd8106f9ca7cc01316513ae66" }, { "url": "https://git.kernel.org/stable/c/e77c80670f2c2bf491da9b173931e1da4677c23a" }, { "url": "https://git.kernel.org/stable/c/8914c3d40870f16429a326e97e4016bedc6ede4c" }, { "url": "https://git.kernel.org/stable/c/455b56209f9615c3902dcc398dd867abb5ade3ab" }, { "url": "https://git.kernel.org/stable/c/fcf21df7d3c50c8ebeb0757df5d21b02dcae4218" }, { "url": "https://git.kernel.org/stable/c/371f7a1b392edc8b7cf449cc7713179b588f2d0e" } ], "title": "md/raid5-ppl: fix use-after-free in ppl_do_flush()", "x_generator": { "engine": "bippy-1.2.0" } } } }