# CVE-2022-48762: arm64: extable: fix load_unaligned_zeropad() reg indices

> A bug in the Linux kernel arm64 exception handler causes arbitrary register corruption and null pointer dereferences, leading to system crashes.

- **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:** 20 Jun 2024
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2022-48762, GHSA-vj7w-cq55-7h2m, UBUNTU-CVE-2022-48762

## What is CVE-2022-48762?

CVE-2022-48762 is a high-severity vulnerability in Linux kernel, published on 20 Jun 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:

arm64: extable: fix load_unaligned_zeropad() reg indices

In ex_handler_load_unaligned_zeropad() we erroneously extract the data and
addr register indices from ex->type rather than ex->data. As ex->type will
contain EX_TYPE_LOAD_UNALIGNED_ZEROPAD (i.e. 4):
 * We'll always treat X0 as the address register, since EX_DATA_REG_ADDR is
   extracted from bits [9:5]. Thus, we may attempt to dereference an
   arbitrary address as X0 may hold an arbitrary value.
 * We'll always treat X4 as the data register, since EX_DATA_REG_DATA is
   extracted from bits [4:0]. Thus we will corrupt X4 and cause arbitrary
   behaviour within load_unaligned_zeropad() and its caller.

Fix this by extracting both values from ex->data as originally intended.

On an MTE-enabled QEMU image we are hitting the following crash:
 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
 Call trace:
  fixup_exception+0xc4/0x108
  __do_kernel_fault+0x3c/0x268
  do_tag_check_fault+0x3c/0x104
  do_mem_abort+0x44/0xf4
  el1_abort+0x40/0x64
  el1h_64_sync_handler+0x60/0xa0
  el1h_64_sync+0x7c/0x80
  link_path_walk+0x150/0x344
  path_openat+0xa0/0x7dc
  do_filp_open+0xb8/0x168
  do_sys_openat2+0x88/0x17c
  __arm64_sys_openat+0x74/0xa0
  invoke_syscall+0x48/0x148
  el0_svc_common+0xb8/0xf8
  do_el0_svc+0x28/0x88
  el0_svc+0x24/0x84
  el0t_64_sync_handler+0x88/0xec
  el0t_64_sync+0x1b4/0x1b8
 Code: f8695a69 71007d1f 540000e0 927df12a (f940014a)

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-48762?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-48762?

Apply the vendor's patch.

## Is CVE-2022-48762 being exploited?

There is no known exploitation of CVE-2022-48762 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-2022-48762 and fix it if it is affected.

What it is: CVE-2022-48762 is a high-severity vulnerability in Linux kernel, published on 20 Jun 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-2022-48762 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-2022-48762/ (Markdown: https://insights.sbomify.com/CVE-2022-48762/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-48762
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-48762
- OSV: https://osv.dev/vulnerability/CVE-2022-48762

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-48762/
Summaries are generated and may contain mistakes; the official description above is the record.
