{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43178", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:55.991Z", "datePublished": "2026-05-06T11:27:51.524Z", "dateUpdated": "2026-08-05T12:26:20.039Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:26:20.039Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nprocfs: fix possible double mmput() in do_procmap_query()\n\nWhen user provides incorrectly sized buffer for build ID for PROCMAP_QUERY\nwe return with -ENAMETOOLONG error. After recent changes this condition\nhappens later, after we unlocked mmap_lock/per-VMA lock and did mmput(),\nso original goto out is now wrong and will double-mmput() mm_struct. Fix\nby jumping further to clean up only vm_file and name_buf." } ], "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 path is reached through a local `ioctl(PROCMAP_QUERY)` on `/proc//maps`; there is no network, adjacent, or physical attack path.\nAC:L - The trigger is deterministic: choose a file-backed VMA with a build ID and pass a nonzero build ID buffer smaller than the parsed build ID. No attacker-uncontrolled race or rare state is required.\nPR:L - An unprivileged local user can open and query `/proc/self/maps`; ptrace-style checks only restrict querying other processes. No real root or namespace-derived administrative capability is needed for self-triggering.\nUI:N - The attacker can perform the mapping and ioctl directly in their own process. No victim user action is required.\nS:U - The vulnerability corrupts kernel memory-management state within the same OS security authority. It is not a VM escape, IOMMU bypass, or cross-authority boundary violation.\nC:H - The double `mmput()` can prematurely run `__mmput()`/`exit_mmap()` and later free an mm still in use, creating use-after-free/refcount corruption of memory-management structures. Under the higher-severity rule, this is treated as capable of enabling high-impact information disclosure.\nI:H - Premature teardown/freeing of a live mm and page-table related state is memory-management corruption with plausible use-after-free exploitation potential. Under the higher-severity rule, this supports high integrity impact.\nA:H - Syzbot observed a kernel `__mmdrop()` warning with `mm == current->mm`, and the bug can tear down or free a live address space. This can cause kernel warnings, crashes, or severe system instability." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/proc/task_mmu.c" ], "versions": [ { "version": "b9b97e6aeb534315f9646b2090d1a5024c6a4e82", "lessThan": "f9fe092084cd04deea18747f58a2304026e76aaa", "status": "affected", "versionType": "git" }, { "version": "cbc03ce3e6ce7e21214c3f02218213574c1a2d08", "lessThan": "8adaff87db143583e08eec4f4e7788f1ef8af94d", "status": "affected", "versionType": "git" }, { "version": "b5cbacd7f86f4f62b8813688c8e73be94e8e1951", "lessThan": "90f5e87c9b75833b9ef3a4415b92c0247f28ab2f", "status": "affected", "versionType": "git" }, { "version": "b5cbacd7f86f4f62b8813688c8e73be94e8e1951", "lessThan": "61dc9f776705d6db6847c101b98fa4f0e9eb6fa3", "status": "affected", "versionType": "git" }, { "version": "6.12.70", "lessThan": "6.12.75", "status": "affected", "versionType": "semver" }, { "version": "6.18.10", "lessThan": "6.18.16", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/proc/task_mmu.c" ], "versions": [ { "version": "6.19", "status": "affected" }, { "version": "0", "lessThan": "6.19", "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": "6.12.70", "versionEndExcluding": "6.12.75" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.10", "versionEndExcluding": "6.18.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/f9fe092084cd04deea18747f58a2304026e76aaa" }, { "url": "https://git.kernel.org/stable/c/8adaff87db143583e08eec4f4e7788f1ef8af94d" }, { "url": "https://git.kernel.org/stable/c/90f5e87c9b75833b9ef3a4415b92c0247f28ab2f" }, { "url": "https://git.kernel.org/stable/c/61dc9f776705d6db6847c101b98fa4f0e9eb6fa3" } ], "title": "procfs: fix possible double mmput() in do_procmap_query()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "affected": [ { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:10" ], "defaultStatus": "unaffected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 10", "vendor": "Red Hat" }, { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:6" ], "defaultStatus": "unknown", "packageName": "kernel", "product": "Red Hat Enterprise Linux 6", "vendor": "Red Hat" }, { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:7" ], "defaultStatus": "unaffected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 7", "vendor": "Red Hat" }, { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:7" ], "defaultStatus": "unaffected", "packageName": "kernel-rt", "product": "Red Hat Enterprise Linux 7", "vendor": "Red Hat" }, { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:8" ], "defaultStatus": "unaffected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 8", "vendor": "Red Hat" }, { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:8" ], "defaultStatus": "unaffected", "packageName": "kernel-rt", "product": "Red Hat Enterprise Linux 8", "vendor": "Red Hat" }, { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:9" ], "defaultStatus": "unaffected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 9", "vendor": "Red Hat" }, { "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": [ "cpe:/o:redhat:enterprise_linux:9" ], "defaultStatus": "unaffected", "packageName": "kernel-rt", "product": "Red Hat Enterprise Linux 9", "vendor": "Red Hat" } ], "datePublic": "2026-05-06T00:00:00.000Z", "descriptions": [ { "lang": "en", "value": "A flaw was found in the Linux kernel's procfs component. A local user, by providing a malformed input buffer during a specific memory mapping query (PROCMAP_QUERY), can trigger an error in how the kernel manages process memory. This can lead to a double release of memory resources, potentially causing the system to crash and resulting in a denial of service (DoS)." } ], "metrics": [ { "other": { "content": { "namespace": "https://access.redhat.com/security/updates/classification/", "value": "Important" }, "type": "Red Hat severity rating" } }, { "cvssV3_1": { "attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1" }, "format": "CVSS" } ], "problemTypes": [ { "descriptions": [ { "cweId": "CWE-1341", "description": "Multiple Releases of Same Resource or Handle", "lang": "en", "type": "CWE" } ] } ], "references": [ { "tags": [ "vdb-entry", "x_refsource_REDHAT" ], "url": "https://access.redhat.com/security/cve/CVE-2026-43178" }, { "name": "RHBZ#2467227", "tags": [ "issue-tracking", "x_refsource_REDHAT" ], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467227" }, { "tags": [ "x_sadp-csaf-vex" ], "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43178.json" } ], "timeline": [ { "lang": "en", "time": "2026-05-06T00:00:00.000Z", "value": "Reported to Red Hat." }, { "lang": "en", "time": "2026-05-06T00:00:00.000Z", "value": "Made public." } ], "title": "kernel: procfs: fix possible double mmput() in do_procmap_query()", "x_adpType": "supplier", "x_generator": { "engine": "sadp-cli 1.0.0" }, "providerMetadata": { "orgId": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "shortName": "redhat-SADP", "dateUpdated": "2026-07-15T00:56:03.022Z" } } ] } }