# CVE-2024-27061: crypto: sun8i-ce - Fix use after free in unprepare

> A use-after-free vulnerability in the Linux kernel's sun8i-ce crypto driver can cause a kernel crash during self-tests.

- **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:** 1 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-40334, BELL-CVE-2024-27061, DEBIAN-CVE-2024-27061, GHSA-rf6j-8jq6-g935, UBUNTU-CVE-2024-27061

## What is CVE-2024-27061?

CVE-2024-27061 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 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:

crypto: sun8i-ce - Fix use after free in unprepare

sun8i_ce_cipher_unprepare should be called before
crypto_finalize_skcipher_request, because client callbacks may
immediately free memory, that isn't needed anymore. But it will be
used by unprepare after free. Before removing prepare/unprepare
callbacks it was handled by crypto engine in crypto_finalize_request.

Usually that results in a pointer dereference problem during a in
crypto selftest.
 Unable to handle kernel NULL pointer dereference at
                                      virtual address 0000000000000030
 Mem abort info:
   ESR = 0x0000000096000004
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x04: level 0 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 user pgtable: 4k pages, 48-bit VAs, pgdp=000000004716d000
 [0000000000000030] pgd=0000000000000000, p4d=0000000000000000
 Internal error: Oops: 0000000096000004 [#1] SMP

This problem is detected by KASAN as well.
 ==================================================================
 BUG: KASAN: slab-use-after-free in sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce]
 Read of size 8 at addr ffff00000dcdc040 by task 1c15000.crypto-/373

 Hardware name: Pine64 PinePhone (1.2) (DT)
 Call trace:
  dump_backtrace+0x9c/0x128
  show_stack+0x20/0x38
  dump_stack_lvl+0x48/0x60
  print_report+0xf8/0x5d8
  kasan_report+0x90/0xd0
  __asan_load8+0x9c/0xc0
  sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce]
  crypto_pump_work+0x354/0x620 [crypto_engine]
  kthread_worker_fn+0x244/0x498
  kthread+0x168/0x178
  ret_from_fork+0x10/0x20

 Allocated by task 379:
  kasan_save_stack+0x3c/0x68
  kasan_set_track+0x2c/0x40
  kasan_save_alloc_info+0x24/0x38
  __kasan_kmalloc+0xd4/0xd8
  __kmalloc+0x74/0x1d0
  alg_test_skcipher+0x90/0x1f0
  alg_test+0x24c/0x830
  cryptomgr_test+0x38/0x60
  kthread+0x168/0x178
  ret_from_fork+0x10/0x20

 Freed by task 379:
  kasan_save_stack+0x3c/0x68
  kasan_set_track+0x2c/0x40
  kasan_save_free_info+0x38/0x60
  __kasan_slab_free+0x100/0x170
  slab_free_freelist_hook+0xd4/0x1e8
  __kmem_cache_free+0x15c/0x290
  kfree+0x74/0x100
  kfree_sensitive+0x80/0xb0
  alg_test_skcipher+0x12c/0x1f0
  alg_test+0x24c/0x830
  cryptomgr_test+0x38/0x60
  kthread+0x168/0x178
  ret_from_fork+0x10/0x20

 The buggy address belongs to the object at ffff00000dcdc000
  which belongs to the cache kmalloc-256 of size 256
 The buggy address is located 64 bytes inside of
  freed 256-byte region [ffff00000dcdc000, ffff00000dcdc100)

Weakness: CWE-476 (NULL Pointer Dereference), CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-27061?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-27061?

Apply the vendor's patch.

## Is CVE-2024-27061 being exploited?

There is no known exploitation of CVE-2024-27061 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-2024-27061 and fix it if it is affected.

What it is: CVE-2024-27061 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 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-2024-27061 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-2024-27061/ (Markdown: https://insights.sbomify.com/CVE-2024-27061/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-27061
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-27061
- OSV: https://osv.dev/vulnerability/CVE-2024-27061

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-27061/
Summaries are generated and may contain mistakes; the official description above is the record.