# CVE-2023-52451: powerpc/pseries/memhp: Fix access beyond end of drmem array

> A local attacker can trigger an out-of-bounds read in the Linux kernel's powerpc memory hotplug code, causing a system crash.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Feb 2024
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-52451, DEBIAN-CVE-2023-52451, GHSA-64r6-8p6g-7r26, UBUNTU-CVE-2023-52451

## What is CVE-2023-52451?

CVE-2023-52451 is a high-severity memory corruption vulnerability in Linux kernel, published on 22 Feb 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

powerpc/pseries/memhp: Fix access beyond end of drmem array

dlpar_memory_remove_by_index() may access beyond the bounds of the
drmem lmb array when the LMB lookup fails to match an entry with the
given DRC index. When the search fails, the cursor is left pointing to
&drmem_info->lmbs[drmem_info->n_lmbs], which is one element past the
last valid entry in the array. The debug message at the end of the
function then dereferences this pointer:

        pr_debug("Failed to hot-remove memory at %llx\n",
                 lmb->base_addr);

This was found by inspection and confirmed with KASAN:

  pseries-hotplug-mem: Attempting to hot-remove LMB, drc index 1234
  ==================================================================
  BUG: KASAN: slab-out-of-bounds in dlpar_memory+0x298/0x1658
  Read of size 8 at addr c000000364e97fd0 by task bash/949

  dump_stack_lvl+0xa4/0xfc (unreliable)
  print_report+0x214/0x63c
  kasan_report+0x140/0x2e0
  __asan_load8+0xa8/0xe0
  dlpar_memory+0x298/0x1658
  handle_dlpar_errorlog+0x130/0x1d0
  dlpar_store+0x18c/0x3e0
  kobj_attr_store+0x68/0xa0
  sysfs_kf_write+0xc4/0x110
  kernfs_fop_write_iter+0x26c/0x390
  vfs_write+0x2d4/0x4e0
  ksys_write+0xac/0x1a0
  system_call_exception+0x268/0x530
  system_call_vectored_common+0x15c/0x2ec

  Allocated by task 1:
   kasan_save_stack+0x48/0x80
   kasan_set_track+0x34/0x50
   kasan_save_alloc_info+0x34/0x50
   __kasan_kmalloc+0xd0/0x120
   __kmalloc+0x8c/0x320
   kmalloc_array.constprop.0+0x48/0x5c
   drmem_init+0x2a0/0x41c
   do_one_initcall+0xe0/0x5c0
   kernel_init_freeable+0x4ec/0x5a0
   kernel_init+0x30/0x1e0
   ret_from_kernel_user_thread+0x14/0x1c

  The buggy address belongs to the object at c000000364e80000
   which belongs to the cache kmalloc-128k of size 131072
  The buggy address is located 0 bytes to the right of
   allocated 98256-byte region [c000000364e80000, c000000364e97fd0)

  ==================================================================
  pseries-hotplug-mem: Failed to hot-remove memory at 0

Log failed lookups with a separate message and dereference the
cursor only when it points to a valid entry.

Weakness: CWE-129 (Improper Validation of Array Index)

## Which versions are affected by CVE-2023-52451?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-52451?

Apply the vendor's patch.

## Is CVE-2023-52451 being exploited?

There is no known exploitation of CVE-2023-52451 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-52451 and fix it if it is affected.

What it is: CVE-2023-52451 is a high-severity memory corruption vulnerability in Linux kernel, published on 22 Feb 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-52451 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-52451/ (Markdown: https://insights.sbomify.com/CVE-2023-52451/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-52451
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-52451
- OSV: https://osv.dev/vulnerability/CVE-2023-52451

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-52451/
Summaries are generated and may contain mistakes; the official description above is the record.