{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64018", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.027Z", "datePublished": "2026-07-19T15:39:12.704Z", "dateUpdated": "2026-08-05T12:38:15.556Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:38:15.556Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: mana: validate rx_req_idx to prevent out-of-bounds array access\n\nIn mana_hwc_rx_event_handler(), rx_req_idx is derived from\nsge->address in DMA-coherent memory. In Confidential VMs\n(SEV-SNP/TDX), this memory is shared unencrypted and HW can modify\nWQE contents at any time. No bounds check exists on rx_req_idx,\nwhich can lead to an out-of-bounds access into reqs[].\n\nAdd bounds check on rx_req_idx in mana_hwc_rx_event_handler() before\nusing it to index the reqs[] array." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "baseScore": 9.3, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is reached via MSI-driven hardware completion processing in the MANA HWC control path (not netdev packet receive), triggered when the Azure hypervisor/host tampers with guest-visible DMA-coherent WQE memory on the same physical compute node.\nAC:L - A malicious host or NIC firmware that can modify shared unencrypted DMA buffers controls both the forged sge->address and the timing of HWC RX completions, allowing reliable out-of-bounds indexing without winning a race or depending on guest state.\nPR:N - Exploitation requires no privileges on the victim guest VM; the attacker operates from the Azure hypervisor/host side by modifying DMA-coherent memory that the guest kernel trusts during HWC response handling.\nUI:N - No victim user action is required; exploitation occurs automatically when the driver processes a hardware completion event on the HWC receive queue.\nS:C - In Confidential VMs the guest relies on host isolation guarantees, but shared unencrypted DMA memory lets a hostile hypervisor cross that CVM security boundary to corrupt guest kernel memory and confidentiality.\nC:H - An out-of-bounds rx_req_idx yields a corrupted hwc_work_request whose buf_va is dereferenced and copied via memcpy in mana_hwc_handle_resp(), enabling arbitrary kernel memory disclosure.\nI:H - The out-of-bounds hwc_work_request supplies attacker-controlled pointers and SGE fields used to repost RX WQEs via mana_hwc_post_rx_wqe(), enabling kernel heap corruption and exploitable memory writes.\nA:H - Indexing reqs[] out of bounds with attacker-controlled values can dereference invalid kernel pointers and corrupt adjacent heap objects, causing kernel oops/panic and denial of service." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/microsoft/mana/hw_channel.c" ], "versions": [ { "version": "ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f", "lessThan": "5ddc715324badd7f2641bc177db1d027b402adae", "status": "affected", "versionType": "git" }, { "version": "ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f", "lessThan": "ff1d5af207bcea857d45fe81505f1bc4b29eaef0", "status": "affected", "versionType": "git" }, { "version": "ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f", "lessThan": "01f7f893d5e1baae995beeb86cd0f3e6bb2a3b01", "status": "affected", "versionType": "git" }, { "version": "ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f", "lessThan": "763a372d344fb12fae566d36ddb46e92454ad58c", "status": "affected", "versionType": "git" }, { "version": "ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f", "lessThan": "fa627a5eaa83fc0261f44ef3769693b886ca6e27", "status": "affected", "versionType": "git" }, { "version": "ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f", "lessThan": "355e9f2b2a7887ca38100127989af3e422ba71d0", "status": "affected", "versionType": "git" }, { "version": "ca9c54d2d6a5ab2430c4eda364c77125d62e5e0f", "lessThan": "b809d0409991b75a6cff846a5ac27c3062953f84", "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/net/ethernet/microsoft/mana/hw_channel.c" ], "versions": [ { "version": "5.13", "status": "affected" }, { "version": "0", "lessThan": "5.13", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.209", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.142", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.92", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.34", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.11", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "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": "5.13", "versionEndExcluding": "5.15.209" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "6.6.142" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "6.12.92" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "6.18.34" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "7.0.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/5ddc715324badd7f2641bc177db1d027b402adae" }, { "url": "https://git.kernel.org/stable/c/ff1d5af207bcea857d45fe81505f1bc4b29eaef0" }, { "url": "https://git.kernel.org/stable/c/01f7f893d5e1baae995beeb86cd0f3e6bb2a3b01" }, { "url": "https://git.kernel.org/stable/c/763a372d344fb12fae566d36ddb46e92454ad58c" }, { "url": "https://git.kernel.org/stable/c/fa627a5eaa83fc0261f44ef3769693b886ca6e27" }, { "url": "https://git.kernel.org/stable/c/355e9f2b2a7887ca38100127989af3e422ba71d0" }, { "url": "https://git.kernel.org/stable/c/b809d0409991b75a6cff846a5ac27c3062953f84" } ], "title": "net: mana: validate rx_req_idx to prevent out-of-bounds array access", "x_generator": { "engine": "bippy-1.2.0" } } } }