CVE-2026-23243

Aliases:UBUNTU-CVE-2026-23243DEBIAN-CVE-2026-23243
Advisory lineage Upstream: 0 Downstream: 56
Modified
Published: 18 Mar 2026, 10:05
Last modified:08 Sept 2026, 08:45

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
v3.1 (cve.org)
EPSS Score
0.13% LOW
0% probability +0.10%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

18 Mar 2026, 10:05
Published
Vulnerability first disclosed
08 Sept 2026, 08:45
Last Modified
Vulnerability information updated

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 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

CVSS Metrics

  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.13%• Percentile: 3%

Techniques & Countermeasures

  • CWE-787•Out-of-bounds Write

    The product writes data past the end, or before the beginning, of the intended buffer.

Affected Systems

  • debian•linux

    < 5.10.257-1 | < 6.1.170-1 | < 6.12.85-1 | < 6.18.14-1

  • debian•linux-6.1

    < 6.1.170-1~deb11u1

  • ubuntu•linux

    all | < 5.15.0-186.196 | < 6.8.0-134.134 | all

  • ubuntu•linux-allwinner-5.19

    all

  • ubuntu•linux-aws

    all | < 5.15.0-1112.119 | < 6.8.0-1060.63 | all

  • ubuntu•linux-aws-5.0

    all

  • ubuntu•linux-aws-5.11

    all

  • ubuntu•linux-aws-5.13

    all

  • ubuntu•linux-aws-5.15

    < 5.15.0-1112.119~20.04.1

  • ubuntu•linux-aws-5.19

    all

  • ubuntu•linux-aws-5.3

    all

  • ubuntu•linux-aws-5.4

    all

  • ubuntu•linux-aws-5.8

    all

  • ubuntu•linux-aws-6.14

    all

  • ubuntu•linux-aws-6.17

    all

  • ubuntu•linux-aws-6.2

    all

  • ubuntu•linux-aws-6.5

    all

  • ubuntu•linux-aws-6.8

    < 6.8.0-1060.63~22.04.1

  • ubuntu•linux-aws-fips

    all | < 5.15.0-1112.119+fips1 | < 6.8.0-1060.63+fips1

  • ubuntu•linux-aws-hwe

    all

  • ubuntu•linux-azure

    all | all | < 5.15.0-1117.126 | < 6.8.0-1063.71 | all

  • ubuntu•linux-azure-4.15

    all

  • ubuntu•linux-azure-5.11

    all

  • ubuntu•linux-azure-5.13

    all

  • ubuntu•linux-azure-5.15

    < 5.15.0-1117.126~20.04.1

  • ubuntu•linux-azure-5.19

    all

  • ubuntu•linux-azure-5.3

    all

  • ubuntu•linux-azure-5.4

    all

  • ubuntu•linux-azure-5.8

    all

  • ubuntu•linux-azure-6.11

    all

  • ubuntu•linux-azure-6.14

    all

  • ubuntu•linux-azure-6.17

    all

  • ubuntu•linux-azure-6.2

    all

  • ubuntu•linux-azure-6.5

    all

  • ubuntu•linux-azure-6.8

    < 6.8.0-1063.71~22.04.1

  • ubuntu•linux-azure-edge

    all

  • ubuntu•linux-azure-fde

    all | < 5.15.0-1117.126 | < 6.8.0-1062.69 | all

  • ubuntu•linux-azure-fde-5.15

    < 5.15.0-1117.126~20.04.2

  • ubuntu•linux-azure-fde-5.19

    all

  • ubuntu•linux-azure-fde-6.14

    all

  • ubuntu•linux-azure-fde-6.2

    all

  • ubuntu•linux-azure-fde-6.8

    < 6.8.0-1062.69~22.04.1

  • ubuntu•linux-azure-fips

    all | < 5.15.0-1117.126+fips1 | < 6.8.0-1062.69+fips1

  • ubuntu•linux-azure-nvidia

    all

  • ubuntu•linux-azure-nvidia-6.14

    all

  • ubuntu•linux-bluefield

    all | all | < 5.15.0-1096.98 | < 6.8.0-1026.30

  • ubuntu•linux-fips

    all | < 5.15.0-186.196+fips1 | < 6.8.0-134.134+fips1

  • ubuntu•linux-gcp

    all | all | < 5.15.0-1112.122 | < 6.8.0-1063.69 | all

  • ubuntu•linux-gcp-4.15

    all

  • ubuntu•linux-gcp-5.11

    all

Showing first 50 affected entries in server-rendered view.

References (38)