CVE-2026-53371

Published Jul 19, 2026

Last updated a month ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/ionic: bound node_desc sysfs read with %.64s node_desc[64] in struct ib_device is not guaranteed to be NUL- terminated. The core IB sysfs handler uses "%.64s" for exactly this reason (drivers/infiniband/core/sysfs.c:1307), since node_desc_store() performs a raw memcpy of up to IB_DEVICE_NODE_DESC_MAX bytes with no NUL termination: memcpy(desc.node_desc, buf, min_t(int, count, IB_DEVICE_NODE_DESC_MAX)); If exactly 64 bytes are written via the node_desc sysfs file, the array contains no NUL byte. The ionic hca_type_show() handler uses unbounded "%s" and will read past the end of node_desc into adjacent fields of struct ib_device until it encounters a NUL. ionic supports IB_DEVICE_MODIFY_NODE_DESC, so this is triggerable by userspace. Match the core handler and bound the format specifier.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

Configurations

Related CVEs

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References

Sources include official advisories and independent security research.