CVE-2026-45837

{"id": "CVE-2026-45837", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "317460317a02a1af512697e6e964298dedd8a163", "lessThan": "723b9fa930cc277c15ce6b9ec9feec828cfac9d7", "versionType": "git"}, {"status": "affected", "version": "317460317a02a1af512697e6e964298dedd8a163", "lessThan": "d18099f19e53250f8ad2801498b88cec29d9107a", "versionType": "git"}, {"status": "affected", "version": "317460317a02a1af512697e6e964298dedd8a163", "lessThan": "201128fcc7b213d27ab77bc4e89488b41796480f", "versionType": "git"}, {"status": "affected", "version": "317460317a02a1af512697e6e964298dedd8a163", "lessThan": "4fddde2a732de60bb97e3307d4eb69ac5f1d2b74", "versionType": "git"}], "programFiles": ["kernel/bpf/arena.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.9"}, {"status": "unaffected", "version": "0", "lessThan": "6.9", "versionType": "semver"}, {"status": "unaffected", "version": "6.12.88", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.30", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.7", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["kernel/bpf/arena.c"], "defaultStatus": "affected"}]}], "published": "2026-05-27T11:16:23.020", "references": [{"url": "https://git.kernel.org/stable/c/201128fcc7b213d27ab77bc4e89488b41796480f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4fddde2a732de60bb97e3307d4eb69ac5f1d2b74", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/723b9fa930cc277c15ce6b9ec9feec828cfac9d7", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/d18099f19e53250f8ad2801498b88cec29d9107a", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix use-after-free in arena_vm_close on fork\n\narena_vm_open() only bumps vml->mmap_count but never registers the\nchild VMA in arena->vma_list. The vml->vma always points at the\nparent VMA, so after parent munmap the pointer dangles. If the child\nthen calls bpf_arena_free_pages(), zap_pages() reads the stale\nvml->vma triggering use-after-free.\n\nFix this by preventing the arena VMA from being inherited across\nfork with VM_DONTCOPY, and preventing VMA splits via the may_split\ncallback.\n\nAlso reject mremap with a .mremap callback returning -EINVAL. A\nsame-size mremap(MREMAP_FIXED) on the full arena VMA reaches\ncopy_vma() through the following path:\n\n check_prep_vma() - returns 0 early: new_len == old_len\n skips VM_DONTEXPAND check\n prep_move_vma() - vm_start == old_addr and\n vm_end == old_addr + old_len\n so may_split is never called\n move_vma()\n copy_vma_and_data()\n copy_vma()\n vm_area_dup() - copies vm_private_data (vml pointer)\n vm_ops->open() - bumps vml->mmap_count\n vm_ops->mremap() - returns -EINVAL, rollback unmaps new VMA\n\nThe refcount ensures the rollback's arena_vm_close does not free\nthe vml shared with the original VMA."}], "lastModified": "2026-06-26T19:09:14.590", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4CCB4364-CBF5-40DD-AB08-D4665BBE06FB", "versionEndExcluding": "6.12.88", "versionStartIncluding": "6.9"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BF39AE08-AE6D-4410-8FBE-76F6BF5BF55B", "versionEndExcluding": "6.18.30", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D0893CA7-9AE6-4DFE-AC75-48967D73AD8E", "versionEndExcluding": "7.0.7", "versionStartIncluding": "6.19"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}