{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43278", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:55.998Z", "datePublished": "2026-05-06T11:29:00.193Z", "dateUpdated": "2026-08-05T12:27:00.162Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:27:00.162Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm: clear cloned request bio pointer when last clone bio completes\n\nStale rq->bio values have been observed to cause double-initialization of\ncloned bios in request-based device-mapper targets, leading to\nuse-after-free and double-free scenarios.\n\nOne such case occurs when using dm-multipath on top of a PCIe NVMe\nnamespace, where cloned request bios are freed during\nblk_complete_request(), but rq->bio is left intact. Subsequent clone\nteardown then attempts to free the same bios again via\nblk_rq_unprep_clone().\n\nThe resulting double-free path looks like:\n\n nvme_pci_complete_batch()\n nvme_complete_batch()\n blk_mq_end_request_batch()\n blk_complete_request() // called on a DM clone request\n bio_endio() // first free of all clone bios\n ...\n rq->end_io() // end_clone_request()\n dm_complete_request(tio->orig)\n dm_softirq_done()\n dm_done()\n dm_end_request()\n blk_rq_unprep_clone() // second free of clone bios\n\nFix this by clearing the clone request's bio pointer when the last cloned\nbio completes, ensuring that later teardown paths do not attempt to free\nalready-released bios." } ], "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 vulnerable request-based device-mapper path is reached by local block I/O, such as reads or writes to a filesystem backed by dm-multipath. It is not itself a network protocol handler, even though network services may indirectly generate disk I/O.\nAC:L - On an affected request-based dm-multipath stack over blk-mq/NVMe, ordinary I/O can drive the deterministic completion path that frees the clone bios and then tears down the clone. No attacker-uncontrolled race is required.\nPR:L - Creating or reconfiguring DM devices requires CAP_SYS_ADMIN, but triggering the bug only requires the ability to issue I/O to an existing affected mapped device, for example through files the local user can read or write. Thus a basic unprivileged local user can reach the vulnerable path.\nUI:N - The attacker can trigger the I/O directly through their own syscalls. No separate victim action is required.\nS:U - The impact remains within the kernel/host security authority. This is a standard local kernel memory-corruption issue, not a VM escape or cross-authority boundary bypass.\nC:H - The stale cloned bio pointer causes use-after-free/double-free of kernel heap objects from the DM bioset. Per kernel CVSS guidance, such memory corruption is treated as capable of enabling high-impact information disclosure.\nI:H - The double-free/use-after-free can corrupt allocator state or allow overlapping/reused kernel objects, which is defensibly exploitable for arbitrary memory modification or code execution. Per guidance, UAF/double-free memory corruption warrants high integrity impact.\nA:H - Even without full exploitation, the double-free/use-after-free can trigger kernel memory corruption, oops, or panic during I/O completion. Repeated attacker-controlled I/O can repeatedly hit the vulnerable path." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/md/dm-rq.c" ], "versions": [ { "version": "ab3e1d3bbab9e973aeb4dd4603251578658a47ff", "lessThan": "8d9ddad561136f7e6a9346767bf97b4d79e38e67", "status": "affected", "versionType": "git" }, { "version": "ab3e1d3bbab9e973aeb4dd4603251578658a47ff", "lessThan": "7daf279c674d515fb22a727a7bbc92aeb35c5442", "status": "affected", "versionType": "git" }, { "version": "ab3e1d3bbab9e973aeb4dd4603251578658a47ff", "lessThan": "e2e738e8dfbbf83bd2bae0467ec4420cc52da42a", "status": "affected", "versionType": "git" }, { "version": "ab3e1d3bbab9e973aeb4dd4603251578658a47ff", "lessThan": "b1c1a2637ebd675aa2d71fee8c70da8791d73850", "status": "affected", "versionType": "git" }, { "version": "ab3e1d3bbab9e973aeb4dd4603251578658a47ff", "lessThan": "83d72091804600ead96dc9e9f518ea56cb4942f6", "status": "affected", "versionType": "git" }, { "version": "ab3e1d3bbab9e973aeb4dd4603251578658a47ff", "lessThan": "fb8a6c18fb9a6561f7a15b58b272442b77a242dd", "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/dm-rq.c" ], "versions": [ { "version": "6.1", "status": "affected" }, { "version": "0", "lessThan": "6.1", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.165", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.128", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.75", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.16", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.6", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "6.1", "versionEndExcluding": "6.1.165" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.6.128" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.12.75" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.18.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.19.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/8d9ddad561136f7e6a9346767bf97b4d79e38e67" }, { "url": "https://git.kernel.org/stable/c/7daf279c674d515fb22a727a7bbc92aeb35c5442" }, { "url": "https://git.kernel.org/stable/c/e2e738e8dfbbf83bd2bae0467ec4420cc52da42a" }, { "url": "https://git.kernel.org/stable/c/b1c1a2637ebd675aa2d71fee8c70da8791d73850" }, { "url": "https://git.kernel.org/stable/c/83d72091804600ead96dc9e9f518ea56cb4942f6" }, { "url": "https://git.kernel.org/stable/c/fb8a6c18fb9a6561f7a15b58b272442b77a242dd" } ], "title": "dm: clear cloned request bio pointer when last clone bio completes", "x_generator": { "engine": "bippy-1.2.0" } } } }