{"api_version":"1","generated_at":"2026-07-26T08:27:14+00:00","cve":"CVE-2026-64449","urls":{"html":"https://cve.report/CVE-2026-64449","api":"https://cve.report/api/cve/CVE-2026-64449.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64449","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64449"},"summary":{"title":"staging: vme_user: bound slave read/write to the kern_buf size","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: vme_user: bound slave read/write to the kern_buf size\n\nThe SLAVE-path helpers buffer_to_user() and buffer_from_user() copy\n'count' bytes into/out of the fixed-size kern_buf (size_buf ==\nPCI_BUF_SIZE == 0x20000, 128 KiB) using *ppos as the offset, without\nbounding *ppos + count against size_buf.\n\nvme_user_write()/vme_user_read() only clamp count to the VME window size\n(image_size = vme_get_size(resource)), which VME_SET_SLAVE sets from the\nuser-supplied slave.size -- validated against the VME address space (up\nto VME_A32_MAX = 4 GiB), not against PCI_BUF_SIZE.  When the window\nexceeds 128 KiB, a write()/read() copies past the kern_buf allocation.\n\nClamp count against size_buf in both helpers, with an early return when\n*ppos is already at/after the buffer end.  *ppos is >= 0 here (the caller\nrejects negative offsets), so size_buf - *ppos cannot wrap.  This mirrors\nthe existing clamp in the MASTER-path helpers resource_to_user() /\nresource_from_user(), and matches the read()/write() convention of a\nshort transfer at end-of-buffer.\n\nFound by static analysis (CodeQL taint tracking + CBMC bounded model\nchecking) and confirmed dynamically under KASAN with the vme_fake bridge:\n\n  BUG: KASAN: slab-out-of-bounds in _copy_from_user+0x2d/0x80\n  Write of size 262144 at addr ffff888004100000 by task trigger/68\n    _copy_from_user+0x2d/0x80\n    vme_user_write+0x13e/0x240 [vme_user]\n    vfs_write+0x1b8/0x7a0\n    ksys_write+0xb8/0x150","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-25 10:17:29","updated_at":"2026-07-25 10:17:29"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/9f32f38265014fac7f5dc9490fb01a638ce6e121","name":"https://git.kernel.org/stable/c/9f32f38265014fac7f5dc9490fb01a638ce6e121","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/65358d89dc9f1c25d9364b2b3ef0f3b47717f9ed","name":"https://git.kernel.org/stable/c/65358d89dc9f1c25d9364b2b3ef0f3b47717f9ed","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/adc8b9c30d716c362646edb45662aa1c641a154a","name":"https://git.kernel.org/stable/c/adc8b9c30d716c362646edb45662aa1c641a154a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/8eff7cd4817e14dbe3b9952cce55ef52d1d38940","name":"https://git.kernel.org/stable/c/8eff7cd4817e14dbe3b9952cce55ef52d1d38940","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/e99f2df433c63c86c93de1e5f08f16e404388756","name":"https://git.kernel.org/stable/c/e99f2df433c63c86c93de1e5f08f16e404388756","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1b495fa0d4927c88d88bf346bf311f2e26e860ed","name":"https://git.kernel.org/stable/c/1b495fa0d4927c88d88bf346bf311f2e26e860ed","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64449","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64449","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f00a86d98a1ec3e99d352cda926fab767ba43b1f 65358d89dc9f1c25d9364b2b3ef0f3b47717f9ed git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f00a86d98a1ec3e99d352cda926fab767ba43b1f adc8b9c30d716c362646edb45662aa1c641a154a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f00a86d98a1ec3e99d352cda926fab767ba43b1f 8eff7cd4817e14dbe3b9952cce55ef52d1d38940 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f00a86d98a1ec3e99d352cda926fab767ba43b1f e99f2df433c63c86c93de1e5f08f16e404388756 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f00a86d98a1ec3e99d352cda926fab767ba43b1f 1b495fa0d4927c88d88bf346bf311f2e26e860ed git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f00a86d98a1ec3e99d352cda926fab767ba43b1f 9f32f38265014fac7f5dc9490fb01a638ce6e121 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.32","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.32 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.178 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.145 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.96 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.39 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.4 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64449","cve":"CVE-2026-64449","epss":"0.002150000","percentile":"0.119910000","score_date":"2026-07-25","updated_at":"2026-07-26 00:12:33"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/staging/vme_user/vme_user.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"65358d89dc9f1c25d9364b2b3ef0f3b47717f9ed","status":"affected","version":"f00a86d98a1ec3e99d352cda926fab767ba43b1f","versionType":"git"},{"lessThan":"adc8b9c30d716c362646edb45662aa1c641a154a","status":"affected","version":"f00a86d98a1ec3e99d352cda926fab767ba43b1f","versionType":"git"},{"lessThan":"8eff7cd4817e14dbe3b9952cce55ef52d1d38940","status":"affected","version":"f00a86d98a1ec3e99d352cda926fab767ba43b1f","versionType":"git"},{"lessThan":"e99f2df433c63c86c93de1e5f08f16e404388756","status":"affected","version":"f00a86d98a1ec3e99d352cda926fab767ba43b1f","versionType":"git"},{"lessThan":"1b495fa0d4927c88d88bf346bf311f2e26e860ed","status":"affected","version":"f00a86d98a1ec3e99d352cda926fab767ba43b1f","versionType":"git"},{"lessThan":"9f32f38265014fac7f5dc9490fb01a638ce6e121","status":"affected","version":"f00a86d98a1ec3e99d352cda926fab767ba43b1f","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/staging/vme_user/vme_user.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.32"},{"lessThan":"2.6.32","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.178","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.145","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.96","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.39","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.178","versionStartIncluding":"2.6.32","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.145","versionStartIncluding":"2.6.32","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.96","versionStartIncluding":"2.6.32","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.39","versionStartIncluding":"2.6.32","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.4","versionStartIncluding":"2.6.32","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc3","versionStartIncluding":"2.6.32","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: vme_user: bound slave read/write to the kern_buf size\n\nThe SLAVE-path helpers buffer_to_user() and buffer_from_user() copy\n'count' bytes into/out of the fixed-size kern_buf (size_buf ==\nPCI_BUF_SIZE == 0x20000, 128 KiB) using *ppos as the offset, without\nbounding *ppos + count against size_buf.\n\nvme_user_write()/vme_user_read() only clamp count to the VME window size\n(image_size = vme_get_size(resource)), which VME_SET_SLAVE sets from the\nuser-supplied slave.size -- validated against the VME address space (up\nto VME_A32_MAX = 4 GiB), not against PCI_BUF_SIZE.  When the window\nexceeds 128 KiB, a write()/read() copies past the kern_buf allocation.\n\nClamp count against size_buf in both helpers, with an early return when\n*ppos is already at/after the buffer end.  *ppos is >= 0 here (the caller\nrejects negative offsets), so size_buf - *ppos cannot wrap.  This mirrors\nthe existing clamp in the MASTER-path helpers resource_to_user() /\nresource_from_user(), and matches the read()/write() convention of a\nshort transfer at end-of-buffer.\n\nFound by static analysis (CodeQL taint tracking + CBMC bounded model\nchecking) and confirmed dynamically under KASAN with the vme_fake bridge:\n\n  BUG: KASAN: slab-out-of-bounds in _copy_from_user+0x2d/0x80\n  Write of size 262144 at addr ffff888004100000 by task trigger/68\n    _copy_from_user+0x2d/0x80\n    vme_user_write+0x13e/0x240 [vme_user]\n    vfs_write+0x1b8/0x7a0\n    ksys_write+0xb8/0x150"}],"providerMetadata":{"dateUpdated":"2026-07-25T08:51:19.537Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/65358d89dc9f1c25d9364b2b3ef0f3b47717f9ed"},{"url":"https://git.kernel.org/stable/c/adc8b9c30d716c362646edb45662aa1c641a154a"},{"url":"https://git.kernel.org/stable/c/8eff7cd4817e14dbe3b9952cce55ef52d1d38940"},{"url":"https://git.kernel.org/stable/c/e99f2df433c63c86c93de1e5f08f16e404388756"},{"url":"https://git.kernel.org/stable/c/1b495fa0d4927c88d88bf346bf311f2e26e860ed"},{"url":"https://git.kernel.org/stable/c/9f32f38265014fac7f5dc9490fb01a638ce6e121"}],"title":"staging: vme_user: bound slave read/write to the kern_buf size","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64449","datePublished":"2026-07-25T08:51:19.537Z","dateReserved":"2026-07-19T15:36:31.788Z","dateUpdated":"2026-07-25T08:51:19.537Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-25 10:17:29","lastModifiedDate":"2026-07-25 10:17:29","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64449","Ordinal":"1","Title":"staging: vme_user: bound slave read/write to the kern_buf size","CVE":"CVE-2026-64449","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64449","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: vme_user: bound slave read/write to the kern_buf size\n\nThe SLAVE-path helpers buffer_to_user() and buffer_from_user() copy\n'count' bytes into/out of the fixed-size kern_buf (size_buf ==\nPCI_BUF_SIZE == 0x20000, 128 KiB) using *ppos as the offset, without\nbounding *ppos + count against size_buf.\n\nvme_user_write()/vme_user_read() only clamp count to the VME window size\n(image_size = vme_get_size(resource)), which VME_SET_SLAVE sets from the\nuser-supplied slave.size -- validated against the VME address space (up\nto VME_A32_MAX = 4 GiB), not against PCI_BUF_SIZE.  When the window\nexceeds 128 KiB, a write()/read() copies past the kern_buf allocation.\n\nClamp count against size_buf in both helpers, with an early return when\n*ppos is already at/after the buffer end.  *ppos is >= 0 here (the caller\nrejects negative offsets), so size_buf - *ppos cannot wrap.  This mirrors\nthe existing clamp in the MASTER-path helpers resource_to_user() /\nresource_from_user(), and matches the read()/write() convention of a\nshort transfer at end-of-buffer.\n\nFound by static analysis (CodeQL taint tracking + CBMC bounded model\nchecking) and confirmed dynamically under KASAN with the vme_fake bridge:\n\n  BUG: KASAN: slab-out-of-bounds in _copy_from_user+0x2d/0x80\n  Write of size 262144 at addr ffff888004100000 by task trigger/68\n    _copy_from_user+0x2d/0x80\n    vme_user_write+0x13e/0x240 [vme_user]\n    vfs_write+0x1b8/0x7a0\n    ksys_write+0xb8/0x150","Type":"Description","Title":"staging: vme_user: bound slave read/write to the kern_buf size"}]}}}