VDB-351527 · CVE-2026-23243 · EUVD-2026-12804

Linux Kernel up to 6.19.3 ib_create_send_mad out-of-bounds

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5.6	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.19.3. Affected by this vulnerability is the function ib_create_send_mad. The manipulation leads to out-of-bounds. This vulnerability is uniquely identified as CVE-2026-23243. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.19.3 and classified as problematic. This issue affects the function ib_create_send_mad. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality. The summary by CVE is:

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 data_len before creating the send buffer. KASAN splat: [ 211.363464] BUG: KASAN: slab-out-of-bounds in ib_create_send_mad+0xa01/0x11b0 [ 211.364077] Write of size 220 at addr ffff88800c3fa1f8 by task spray_thread/102 [ 211.365867] ib_create_send_mad+0xa01/0x11b0 [ 211.365887] ib_umad_write+0x853/0x1c80

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-23243 since 01/13/2026. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 311783 (Debian dla-4561 : linux-config-6.1 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4 or 7.0-rc1 eliminates this vulnerability. Applying the patch 1371ef6b1ecf3676b8942f5dfb3634fb0648128e/362e45fd9069ffa1523f9f1633b606ebf72060d7/6eb2919474ca105c5b13d19574e25f0ddcf19ca2/a6a3e4af10993cb9e4b8f0548680aba0ab5f3b0d/9c80d688f402539dfc8f336de1380d6b4ee14316/205955f29c26330b1dc7fdeadd5bb97c38e26f56/52ab82cc5cf8ada5c3fb6ffe8f32fdb2fc27a34b/5551b02fdbfd85a325bb857f3a8f9c9f33397ed2 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (311783), EUVD (EUVD-2026-12804) and CERT Bund (WID-SEC-2026-0774). Be aware that VulDB is the high quality source for vulnerability data.

Affected

Google Container-Optimized OS
Debian Linux
Amazon Linux 2
Red Hat Enterprise Linux
SUSE Linux
Oracle Linux
SUSE openSUSE
RESF Rocky Linux
Open Source Linux Kernel

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.6

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.8
CNA Vector (Linux): 🔒

CVSSv2info

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 311783
Nessus Name: Debian dla-4561 : linux-config-6.1 - security update

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Timelineinfo

01/13/2026 CVE reserved
03/18/2026 +64 days Advisory disclosed
03/18/2026 +0 days VulDB entry created
06/24/2026 +97 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CNA: Linux
CVE: CVE-2026-23243 (🔒)

GCVE (CVE): GCVE-0-2026-23243
GCVE (VulDB): GCVE-100-351527
EUVD: 🔒
CERT Bund: WID-SEC-2026-0774 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 03/18/2026 12:01
Updated: 06/24/2026 01:43
Changes: 03/18/2026 12:01 (58), 03/18/2026 12:24 (1), 03/18/2026 14:48 (7), 04/29/2026 21:48 (1), 05/03/2026 18:47 (2), 05/21/2026 22:07 (12), 06/24/2026 01:43 (1)
Complete: 🔍
Cache ID: 216::103