CVE-2026-90435
RDMA/mlx5: Fix integer overflow of user QP buffer size
Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix integer overflow of user QP buffer size set_user_buf_size() computes the QP buffer size by left-shifting the user-supplied rq.wqe_cnt and rq.wqe_shift values as signed integers. A sufficiently large rq.wqe_cnt causes signed integer overflow, which is undefined behavior, and yields a small or negative buf_size, causing ib_umem_get() to map a buffer smaller than the hardware will actually write into. Replace the shifts and addition with check_shl_overflow() and check_add_overflow(), rejecting invalid user inputs. Moreover, guard the identical shift computing qp->sq.offset in _create_user_qp() before set_user_buf_size() is reached.
INFO
Published Date :
Sept. 17, 2026, 5:17 p.m.
Last Modified :
Sept. 18, 2026, 6:17 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Apply the patch for RDMA/mlx5 integer overflow.
- Replace shifts with overflow checking functions.
- Reject invalid user inputs for buffer size.
- Guard against identical shifts in _create_user_qp.
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-2026-90435.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-90435 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-2026-90435
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-2026-90435 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-90435 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.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 18, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 17, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix integer overflow of user QP buffer size set_user_buf_size() computes the QP buffer size by left-shifting the user-supplied rq.wqe_cnt and rq.wqe_shift values as signed integers. A sufficiently large rq.wqe_cnt causes signed integer overflow, which is undefined behavior, and yields a small or negative buf_size, causing ib_umem_get() to map a buffer smaller than the hardware will actually write into. Replace the shifts and addition with check_shl_overflow() and check_add_overflow(), rejecting invalid user inputs. Moreover, guard the identical shift computing qp->sq.offset in _create_user_qp() before set_user_buf_size() is reached. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/90xxx/CVE-2026-90435.json">CVE-2026-90435</a> Added Reference https://git.kernel.org/stable/c/42fb8aefffff5b458aaa66803364a16e0ea44129 Added Reference https://git.kernel.org/stable/c/5b6cfc6d7ff0959dd9766fdc24286a253b59ca77 Added Reference https://git.kernel.org/stable/c/c845e5e05140ea1bc64a5b1107942d93c876034d Added Reference https://git.kernel.org/stable/c/ccce6b7ef1d7efc59ccba3421e1339c6e63a3d20 Added Reference https://git.kernel.org/stable/c/d7fa2ff72ad1861eac194a4e0075d504ba8c246e Added Reference https://git.kernel.org/stable/c/d99622e40aaa910ade681dfd4dc0fa240a011331 Added Reference https://git.kernel.org/stable/c/dec47e4b0fe34afdf38caa72b4408ba95502e5de Added Reference https://git.kernel.org/stable/c/f917707f0de0832b8ab582391b1f64e549995c6c