CVE-2026-74584 — RDMA/bnxt_re: zero shared page before exposing to userspace
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().
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < 53c97e9882f4e747b4ac31b211317c2eba541af9≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < 9896bdfd21d918e9f26a52bc6109cc77970ee0b1≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < 9128c2411b83a64c0a69d2ff059c741bde25a9cc≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < c19b360fa10c521c0b681875cdaa51545d45a491≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < a3ed2daab02b2a706e882ad31b5c3c4f33cb5bb1≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < e2b143df29003d2704b51f62e9297006953dbacb≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < c75f8ce4baa29ae57fe615c6a2c5101f59b8b89a≥ 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and < f6b079629becfa977f9c51fe53ad2e6dcc55ef44 and 1 moreversion 4.11 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.1 | CVSS 3.1 | High | 2.5 | 4.0 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.1 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 7.1 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.18%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- CVSS changed · 7.1
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
10 on the record
- git.kernel.org/stable/c/f6b079629becfa977f9c51fe53ad2e6dcc55ef44
- git.kernel.org/stable/c/e2b143df29003d2704b51f62e9297006953dbacb
- git.kernel.org/stable/c/c19b360fa10c521c0b681875cdaa51545d45a491
- git.kernel.org/stable/c/53c97e9882f4e747b4ac31b211317c2eba541af9
- git.kernel.org/stable/c/9128c2411b83a64c0a69d2ff059c741bde25a9cc
- nvd.nist.gov/vuln/detail/CVE-2026-74584
- git.kernel.org/stable/c/c75f8ce4baa29ae57fe615c6a2c5101f59b8b89a
- git.kernel.org/stable/c/9896bdfd21d918e9f26a52bc6109cc77970ee0b1
- github.com/advisories/GHSA-j6vr-r53f-g3jf
- git.kernel.org/stable/c/a3ed2daab02b2a706e882ad31b5c3c4f33cb5bb1
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 12h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 12h
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 1d
- Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 1d
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-74584 is "RDMA/bnxt_re: zero shared page before exposing to userspace", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.1 describes technical severity. EPSS 0.18% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.