Incorrect Conversion between Numeric Types Affecting kernel-tools package, versions *


Severity

Recommended
medium

Based on CentOS security rating.

Threat Intelligence

EPSS
0.01% (2nd percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-CENTOS10-KERNELTOOLS-16371501
  • published4 May 2026
  • disclosed1 May 2026

Introduced: 1 May 2026

NewCVE-2026-31774  (opens in a new tab)
CWE-681  (opens in a new tab)

How to fix?

There is no fixed version for Centos:10 kernel-tools.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-tools package and not the kernel-tools package as distributed by Centos. See How to fix? for Centos:10 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

io_uring/net: fix slab-out-of-bounds read in io_bundle_nbufs()

sqe->len is __u32 but gets stored into sr->len which is int. When userspace passes sqe->len values exceeding INT_MAX (e.g. 0xFFFFFFFF), sr->len overflows to a negative value. This negative value propagates through the bundle recv/send path:

  1. io_recv(): sel.val = sr->len (ssize_t gets -1)
  2. io_recv_buf_select(): arg.max_len = sel->val (size_t gets 0xFFFFFFFFFFFFFFFF)
  3. io_ring_buffers_peek(): buf->len is not clamped because max_len is astronomically large
  4. iov[].iov_len = 0xFFFFFFFF flows into io_bundle_nbufs()
  5. io_bundle_nbufs(): min_t(int, 0xFFFFFFFF, ret) yields -1, causing ret to increase instead of decrease, creating an infinite loop that reads past the allocated iov[] array

This results in a slab-out-of-bounds read in io_bundle_nbufs() from the kmalloc-64 slab, as nbufs increments past the allocated iovec entries.

BUG: KASAN: slab-out-of-bounds in io_bundle_nbufs+0x128/0x160 Read of size 8 at addr ffff888100ae05c8 by task exp/145 Call Trace: io_bundle_nbufs+0x128/0x160 io_recv_finish+0x117/0xe20 io_recv+0x2db/0x1160

Fix this by rejecting negative sr->len values early in both io_sendmsg_prep() and io_recvmsg_prep(). Since sqe->len is __u32, any value > INT_MAX indicates overflow and is not a valid length.

CVSS Base Scores

version 3.1