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CVE-2026-23243
published 2026-03-18

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_len from…

PriorityP341high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.13%
3.0th percentile
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

Affected

53 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.18.14-1 (forky)linux 6.18.14-1 (forky)
linuxlinux
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < 1371ef6b1ecf3676b8942f5dfb3634fb0648128e1371ef6b1ecf3676b8942f5dfb3634fb0648128e
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < 362e45fd9069ffa1523f9f1633b606ebf72060d7362e45fd9069ffa1523f9f1633b606ebf72060d7
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < 6eb2919474ca105c5b13d19574e25f0ddcf19ca26eb2919474ca105c5b13d19574e25f0ddcf19ca2
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < a6a3e4af10993cb9e4b8f0548680aba0ab5f3b0da6a3e4af10993cb9e4b8f0548680aba0ab5f3b0d
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < 9c80d688f402539dfc8f336de1380d6b4ee143169c80d688f402539dfc8f336de1380d6b4ee14316
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < 205955f29c26330b1dc7fdeadd5bb97c38e26f56205955f29c26330b1dc7fdeadd5bb97c38e26f56
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < 52ab82cc5cf8ada5c3fb6ffe8f32fdb2fc27a34b52ab82cc5cf8ada5c3fb6ffe8f32fdb2fc27a34b
linuxlinux>= 2be8e3ee8efd6f99ce454115c29d09750915021a < 5551b02fdbfd85a325bb857f3a8f9c9f33397ed25551b02fdbfd85a325bb857f3a8f9c9f33397ed2
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.18.14-16.18.14-1
linuxlinux_kernel>= 2.6.24 < 5.10.2525.10.252
linuxlinux_kernel>= 2.6.24.1 < 5.10.2525.10.252
linuxlinux_kernel>= 5.11 < 5.15.2025.15.202
linuxlinux_kernel>= 5.11.0 < 5.15.2025.15.202
linuxlinux_kernel>= 5.16 < 6.1.1656.1.165
linuxlinux_kernel>= 5.16.0 < 6.1.1656.1.165
linuxlinux_kernel>= 6.13 < 6.18.146.18.14
linuxlinux_kernel>= 6.13.0 < 6.18.146.18.14
linuxlinux_kernel>= 6.19 < 6.19.46.19.4
linuxlinux_kernel>= 6.19.0 < 6.19.46.19.4
linuxlinux_kernel>= 6.2 < 6.6.1286.6.128
linuxlinux_kernel>= 6.2.0 < 6.6.1286.6.128
linuxlinux_kernel>= 6.7 < 6.12.756.12.75

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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