CVE-2026-74378
RDMA/rxe: Fix TOCTOU heap overflow in get_srq_wqe
Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Fix TOCTOU heap overflow in get_srq_wqe get_srq_wqe() reads wqe->dma.num_sge from the shared receive queue buffer, which is mapped into userspace. It validates num_sge against max_sge, but then re-reads the same field to calculate the memcpy size. A concurrent userspace thread can modify num_sge between validation and use, causing a heap buffer overflow when copying the WQE into qp->resp.srq_wqe. Read num_sge into a local variable and use it for both the bounds check and the size calculation.
INFO
Published Date :
Aug. 15, 2026, 6:22 a.m.
Last Modified :
Aug. 15, 2026, 6:22 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-74378
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Read num_sge into a local variable.
- Use local variable for bounds check.
- Use local variable for size calculation.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-74378.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74378 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-74378
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-74378 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74378 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '8700e3e7c4857d28ebaa824509934556da0b3e76', 'lessThan': '3cfa2a3adc51b7c57729961a03446962ff10e3d2', 'versionType': 'git'}, {'status': 'affected', 'version': '8700e3e7c4857d28ebaa824509934556da0b3e76', 'lessThan': 'cd19a6345e3727adafafa5954b58b13c92e13b80', 'versionType': 'git'}, {'status': 'affected', 'version': '8700e3e7c4857d28ebaa824509934556da0b3e76', 'lessThan': '3e07ea9579dc9553d2285c26c2823931358aa3b8', 'versionType': 'git'}, {'status': 'affected', 'version': '8700e3e7c4857d28ebaa824509934556da0b3e76', 'lessThan': '02558c86b6b761063e9399e6b939984500327ef1', 'versionType': 'git'}, {'status': 'affected', 'version': '8700e3e7c4857d28ebaa824509934556da0b3e76', 'lessThan': 'b9800d7953d119bcc068c74587d48e4ba0313629', 'versionType': 'git'}, {'status': 'affected', 'version': '8700e3e7c4857d28ebaa824509934556da0b3e76', 'lessThan': '22b8fbded65b8c441b634a185f8da67657df6c50', 'versionType': 'git'}], 'programFiles': ['drivers/infiniband/sw/rxe/rxe_resp.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.8'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.8', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/infiniband/sw/rxe/rxe_resp.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Fix TOCTOU heap overflow in get_srq_wqe get_srq_wqe() reads wqe->dma.num_sge from the shared receive queue buffer, which is mapped into userspace. It validates num_sge against max_sge, but then re-reads the same field to calculate the memcpy size. A concurrent userspace thread can modify num_sge between validation and use, causing a heap buffer overflow when copying the WQE into qp->resp.srq_wqe. Read num_sge into a local variable and use it for both the bounds check and the size calculation. Added Reference https://git.kernel.org/stable/c/02558c86b6b761063e9399e6b939984500327ef1 Added Reference https://git.kernel.org/stable/c/22b8fbded65b8c441b634a185f8da67657df6c50 Added Reference https://git.kernel.org/stable/c/3cfa2a3adc51b7c57729961a03446962ff10e3d2 Added Reference https://git.kernel.org/stable/c/3e07ea9579dc9553d2285c26c2823931358aa3b8 Added Reference https://git.kernel.org/stable/c/b9800d7953d119bcc068c74587d48e4ba0313629 Added Reference https://git.kernel.org/stable/c/cd19a6345e3727adafafa5954b58b13c92e13b80