CVE-2026-74584 (GCVE-0-2026-74584)
Vulnerability from cvelistv5
Published
2026-08-22 14:28
Modified
2026-08-25 05:40
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: zero shared page before exposing to userspace
bnxt_re_alloc_ucontext() allocates uctx->shpg via
__get_free_page(GFP_KERNEL). The buddy allocator does not zero pages
without __GFP_ZERO, so the page contains stale kernel data from
whatever object most recently freed it.
The page is then mapped into userspace via vm_insert_page() under
BNXT_RE_MMAP_SH_PAGE in bnxt_re_mmap(). The driver only ever writes
4 bytes (a u32 AVID) at offset BNXT_RE_AVID_OFFT (0x10) inside
bnxt_re_create_ah(); the remaining 4092 bytes of the page are exposed
to userspace unsanitised, leaking kernel memory contents.
Any user with access to /dev/infiniband/uverbsX on a host with a
bnxt_re device (typically rdma group membership) can read this data
via a single mmap() at pgoff 0 after IB_USER_VERBS_CMD_GET_CONTEXT.
Other shared pages in the same file already use get_zeroed_page()
correctly:
drivers/infiniband/hw/bnxt_re/ib_verbs.c
srq->uctx_srq_page = (void *)get_zeroed_page(GFP_KERNEL);
cq->uctx_cq_page = (void *)get_zeroed_page(GFP_KERNEL);
uctx->shpg is the only outlier. Bring it in line with the existing
convention by switching to get_zeroed_page().
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 Version: 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 |
||
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/infiniband/hw/bnxt_re/ib_verbs.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "53c97e9882f4e747b4ac31b211317c2eba541af9",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
},
{
"lessThan": "9896bdfd21d918e9f26a52bc6109cc77970ee0b1",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
},
{
"lessThan": "9128c2411b83a64c0a69d2ff059c741bde25a9cc",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
},
{
"lessThan": "c19b360fa10c521c0b681875cdaa51545d45a491",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
},
{
"lessThan": "a3ed2daab02b2a706e882ad31b5c3c4f33cb5bb1",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
},
{
"lessThan": "e2b143df29003d2704b51f62e9297006953dbacb",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
},
{
"lessThan": "c75f8ce4baa29ae57fe615c6a2c5101f59b8b89a",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
},
{
"lessThan": "f6b079629becfa977f9c51fe53ad2e6dcc55ef44",
"status": "affected",
"version": "1ac5a404797523cedaf424a3aaa3cf8f9548dff8",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/infiniband/hw/bnxt_re/ib_verbs.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "4.11"
},
{
"lessThan": "4.11",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.260",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.211",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.177",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.144",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.95",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.37",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.14",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.10.260",
"versionStartIncluding": "4.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.211",
"versionStartIncluding": "4.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.177",
"versionStartIncluding": "4.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.144",
"versionStartIncluding": "4.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.95",
"versionStartIncluding": "4.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.37",
"versionStartIncluding": "4.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.0.14",
"versionStartIncluding": "4.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1",
"versionStartIncluding": "4.11",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/bnxt_re: zero shared page before exposing to userspace\n\nbnxt_re_alloc_ucontext() allocates uctx-\u003eshpg via\n__get_free_page(GFP_KERNEL). The buddy allocator does not zero pages\nwithout __GFP_ZERO, so the page contains stale kernel data from\nwhatever object most recently freed it.\n\nThe page is then mapped into userspace via vm_insert_page() under\nBNXT_RE_MMAP_SH_PAGE in bnxt_re_mmap(). The driver only ever writes\n4 bytes (a u32 AVID) at offset BNXT_RE_AVID_OFFT (0x10) inside\nbnxt_re_create_ah(); the remaining 4092 bytes of the page are exposed\nto userspace unsanitised, leaking kernel memory contents.\n\nAny user with access to /dev/infiniband/uverbsX on a host with a\nbnxt_re device (typically rdma group membership) can read this data\nvia a single mmap() at pgoff 0 after IB_USER_VERBS_CMD_GET_CONTEXT.\n\nOther shared pages in the same file already use get_zeroed_page()\ncorrectly:\n\n drivers/infiniband/hw/bnxt_re/ib_verbs.c\n srq-\u003euctx_srq_page = (void *)get_zeroed_page(GFP_KERNEL);\n cq-\u003euctx_cq_page = (void *)get_zeroed_page(GFP_KERNEL);\n\nuctx-\u003eshpg is the only outlier. Bring it in line with the existing\nconvention by switching to get_zeroed_page()."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.1,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The leak is triggered only through local access to /dev/infiniband/uverbs* via ioctl GET_CONTEXT and mmap(pgoff 0); bnxt_re_mmap maps the shared page with vm_insert_page, and remote RoCE/IB packet handling never reaches this uverbs allocation path.\nAC:L - On a host with bnxt_re loaded, opening uverbs, issuing GET_CONTEXT, and mmap at offset 0 deterministically exposes the unstale page; the attacker controls all syscall parameters and needs no race, special memory layout, or victim-specific state.\nPR:N - Kernel uverbs character devices are created world-accessible (mode 0666) via uverbs_devnode, and ib_uverbs_open performs no capability or root check beyond netns access, so any local process can open the device and allocate a bnxt_re ucontext.\nUI:N - Exploitation requires only attacker-driven open/ioctl/mmap/read syscalls on their own uverbs file descriptor; no cooperative victim action such as mounting filesystems, opening files, or clicking links is needed.\nS:C - On HPC/cloud hosts exposing bnxt_re to tenant containers or shared RDMA workloads, mmap of unstale host-kernel buddy pages leaks host kernel memory across the container/tenant security boundary into an unprivileged workload\u0027s address space.\nC:H - __get_free_page without __GFP_ZERO leaves up to 4092 bytes of stale kernel heap/slack data readable per ucontext; repeated opens yield additional pages, disclosing kernel pointers, structures, and other sensitive material beyond a few-byte bounded leak.\nI:N - The flaw only exposes existing kernel memory contents to userspace via mmap; it does not corrupt, overwrite, or modify kernel objects, grant write primitives, or enable code execution through the shared page mapping.\nA:N - Reading the unstale mapped page does not trigger kernel oops, panic, hang, or resource exhaustion; the vulnerable path completes normally and availability is unaffected aside from normal per-context page allocation."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-25T05:40:11.315Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/53c97e9882f4e747b4ac31b211317c2eba541af9"
},
{
"url": "https://git.kernel.org/stable/c/9896bdfd21d918e9f26a52bc6109cc77970ee0b1"
},
{
"url": "https://git.kernel.org/stable/c/9128c2411b83a64c0a69d2ff059c741bde25a9cc"
},
{
"url": "https://git.kernel.org/stable/c/c19b360fa10c521c0b681875cdaa51545d45a491"
},
{
"url": "https://git.kernel.org/stable/c/a3ed2daab02b2a706e882ad31b5c3c4f33cb5bb1"
},
{
"url": "https://git.kernel.org/stable/c/e2b143df29003d2704b51f62e9297006953dbacb"
},
{
"url": "https://git.kernel.org/stable/c/c75f8ce4baa29ae57fe615c6a2c5101f59b8b89a"
},
{
"url": "https://git.kernel.org/stable/c/f6b079629becfa977f9c51fe53ad2e6dcc55ef44"
}
],
"title": "RDMA/bnxt_re: zero shared page before exposing to userspace",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-74584",
"datePublished": "2026-08-22T14:28:07.988Z",
"dateReserved": "2026-08-15T05:44:03.918Z",
"dateUpdated": "2026-08-25T05:40:11.315Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…