CVE-2026-23243Incorrect Calculation of Buffer Size in Linux

Severity
7.8HIGHNVD
EPSS
0.0%
top 97.70%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedMar 18

Description

In the Linux kernel, the following vulnerability has been resolved: RDMA/umad: Reject negative data_len in ib_umad_write ib_umad_write computes data_len from user-controlled count and the MAD header sizes. With a mismatched user MAD header size and RMPP header length, data_len can become negative and reach ib_create_send_mad(). This can make the padding calculation exceed the segment size and trigger an out-of-bounds memset in alloc_send_rmpp_list(). Add an explicit check to reject negative d

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.8 | Impact: 5.9

Affected Packages3 packages

Linuxlinux/linux_kernel2.6.245.10.252+6
Debianlinux/linux_kernel< 6.18.14-1
CVEListV5linux/linux2be8e3ee8efd6f99ce454115c29d09750915021a1371ef6b1ecf3676b8942f5dfb3634fb0648128e+8

🔴Vulnerability Details

4
OSV
RDMA/umad: Reject negative data_len in ib_umad_write2026-03-18
CVEList
RDMA/umad: Reject negative data_len in ib_umad_write2026-03-18
GHSA
GHSA-85rq-57vx-88q2: In the Linux kernel, the following vulnerability has been resolved: RDMA/umad: Reject negative data_len in ib_umad_write ib_umad_write computes data2026-03-18
OSV
CVE-2026-23243: In the Linux kernel, the following vulnerability has been resolved: RDMA/umad: Reject negative data_len in ib_umad_write ib_umad_write computes data_l2026-03-18

📋Vendor Advisories

3
Red Hat
kernel: Linux kernel: Denial of service and memory corruption in RDMA umad2026-03-18
Microsoft
RDMA/umad: Reject negative data_len in ib_umad_write2026-03-10
Debian
CVE-2026-23243: linux - In the Linux kernel, the following vulnerability has been resolved: RDMA/umad: ...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-23243 Impact, Exploitability, and Mitigation Steps | Wiz
CVE-2026-23243 — Incorrect Calculation of Buffer Size | cvebase