{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-97990", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:18:58.209Z", "datePublished": "2026-09-25T10:23:23.226Z", "dateUpdated": "2026-09-25T14:41:47.453Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-25T14:41:47.453Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvdpa_sim_net: check TX pull result before RX copy\n\nvringh_iov_pull_iotlb() returns a signed byte count. A failed TX pull is\ncurrently added to the unsigned byte counter and then passed as a size_t\nlength to receive_filter() and vringh_iov_push_iotlb(). A negative error\ncan therefore become a large length in the RX path.\n\nHandle non-positive pull results before every length use. Count the TX\nerror and complete the consumed TX descriptor with zero bytes.\n\nI found this bug myself, though the patch was written with AI assistance." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The malformed input is a virtqueue TX descriptor with an unmapped address, written into the vring by whoever drives the vdpa_sim_net device (a guest via vhost-vdpa or a local vhost-vdpa user). vdpasim_net_work() processes it and no network protocol carries it.\nAC:H - Once reached, the failed vringh_iov_pull_iotlb() is deterministic. But it requires an admin to create a vdpa_sim_net device (a test-only simulator under RUNTIME_TESTING_MENU) and assign it to the attacker's VM or process, a configuration the attacker cannot produce.\nPR:L - Device creation needs GENL_ADMIN_PERM in init_net (not reachable via user namespaces). The attacker is the guest or process given the device, which only needs ordinary control of its own virtqueues and no host privileges.\nUI:N - The attacker queues a broadcast TX frame, then a TX descriptor that fails IOTLB translation, plus large RX descriptors, all on their own rings. No victim action is needed.\nS:C - A guest driving vdpa_sim_net through vhost-vdpa causes the host kernel to copy host heap memory into guest-visible RX buffers, crossing the VM-to-host boundary.\nC:H - The negative read, cast to size_t, is passed to vringh_iov_push_iotlb(). It copies from the PAGE_SIZE net->buffer up to the attacker-sized RX iov, leaking adjacent host kernel heap (an out-of-bounds read not limited to a few bytes) into attacker memory.\nI:N - The overlong copy only reads kernel memory and writes into the attacker's own RX buffers; no kernel memory is written. The only other effect is corrupted tx_bytes statistics.\nA:H - A large RX descriptor chain makes the out-of-bounds read of net->buffer run into unmapped memory, oopsing the host kernel and taking down every guest on it." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/vdpa/vdpa_sim/vdpa_sim_net.c" ], "versions": [ { "version": "cfe226892913a448e83e7a19db93862baa3cb99c", "lessThan": "c001abcde865b74231da8f1412c3217dbf66781e", "status": "affected", "versionType": "git" }, { "version": "cfe226892913a448e83e7a19db93862baa3cb99c", "lessThan": "3af20238a09ca180d66623e3bed16b64e9975f39", "status": "affected", "versionType": "git" }, { "version": "cfe226892913a448e83e7a19db93862baa3cb99c", "lessThan": "2bbf1c1f69991e28787e02b0a2f826289d5fc730", "status": "affected", "versionType": "git" }, { "version": "cfe226892913a448e83e7a19db93862baa3cb99c", "lessThan": "0d195797a80b77f2ec56718cd26d3ee65d0093e8", "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/vdpa/vdpa_sim/vdpa_sim_net.c" ], "versions": [ { "version": "5.19", "status": "affected" }, { "version": "0", "lessThan": "5.19", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.7", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3-rc3", "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": "5.19", "versionEndExcluding": "6.12.111" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "6.18.53" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "7.2.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "7.3-rc3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c001abcde865b74231da8f1412c3217dbf66781e" }, { "url": "https://git.kernel.org/stable/c/3af20238a09ca180d66623e3bed16b64e9975f39" }, { "url": "https://git.kernel.org/stable/c/2bbf1c1f69991e28787e02b0a2f826289d5fc730" }, { "url": "https://git.kernel.org/stable/c/0d195797a80b77f2ec56718cd26d3ee65d0093e8" } ], "title": "vdpa_sim_net: check TX pull result before RX copy", "x_generator": { "engine": "bippy-1.2.0" } } } }