# CVE-2024-49953: net/mlx5e: Fix crash caused by calling __xfrm_state_delete() twice

> A use-after-free vulnerability in the Linux kernel's mlx5e driver allows a local attacker to cause a system crash via double deletion of xfrm state.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 21 Oct 2024
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2024-49953, DEBIAN-CVE-2024-49953, GHSA-8qrg-fxff-9fcm, UBUNTU-CVE-2024-49953

## What is CVE-2024-49953?

CVE-2024-49953 is a medium-severity use after free vulnerability in Linux kernel, published on 21 Oct 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:

net/mlx5e: Fix crash caused by calling __xfrm_state_delete() twice

The km.state is not checked in driver's delayed work. When
xfrm_state_check_expire() is called, the state can be reset to
XFRM_STATE_EXPIRED, even if it is XFRM_STATE_DEAD already. This
happens when xfrm state is deleted, but not freed yet. As
__xfrm_state_delete() is called again in xfrm timer, the following
crash occurs.

To fix this issue, skip xfrm_state_check_expire() if km.state is not
XFRM_STATE_VALID.

 Oops: general protection fault, probably for non-canonical address 0xdead000000000108: 0000 [#1] SMP
 CPU: 5 UID: 0 PID: 7448 Comm: kworker/u102:2 Not tainted 6.11.0-rc2+ #1
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
 Workqueue: mlx5e_ipsec: eth%d mlx5e_ipsec_handle_sw_limits [mlx5_core]
 RIP: 0010:__xfrm_state_delete+0x3d/0x1b0
 Code: 0f 84 8b 01 00 00 48 89 fd c6 87 c8 00 00 00 05 48 8d bb 40 10 00 00 e8 11 04 1a 00 48 8b 95 b8 00 00 00 48 8b 85 c0 00 00 00 <48> 89 42 08 48 89 10 48 8b 55 10 48 b8 00 01 00 00 00 00 ad de 48
 RSP: 0018:ffff88885f945ec8 EFLAGS: 00010246
 RAX: dead000000000122 RBX: ffffffff82afa940 RCX: 0000000000000036
 RDX: dead000000000100 RSI: 0000000000000000 RDI: ffffffff82afb980
 RBP: ffff888109a20340 R08: ffff88885f945ea0 R09: 0000000000000000
 R10: 0000000000000000 R11: ffff88885f945ff8 R12: 0000000000000246
 R13: ffff888109a20340 R14: ffff88885f95f420 R15: ffff88885f95f400
 FS:  0000000000000000(0000) GS:ffff88885f940000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f2163102430 CR3: 00000001128d6001 CR4: 0000000000370eb0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  <IRQ>
  ? die_addr+0x33/0x90
  ? exc_general_protection+0x1a2/0x390
  ? asm_exc_general_protection+0x22/0x30
  ? __xfrm_state_delete+0x3d/0x1b0
  ? __xfrm_state_delete+0x2f/0x1b0
  xfrm_timer_handler+0x174/0x350
  ? __xfrm_state_delete+0x1b0/0x1b0
  __hrtimer_run_queues+0x121/0x270
  hrtimer_run_softirq+0x88/0xd0
  handle_softirqs+0xcc/0x270
  do_softirq+0x3c/0x50
  </IRQ>
  <TASK>
  __local_bh_enable_ip+0x47/0x50
  mlx5e_ipsec_handle_sw_limits+0x7d/0x90 [mlx5_core]
  process_one_work+0x137/0x2d0
  worker_thread+0x28d/0x3a0
  ? rescuer_thread+0x480/0x480
  kthread+0xb8/0xe0
  ? kthread_park+0x80/0x80
  ret_from_fork+0x2d/0x50
  ? kthread_park+0x80/0x80
  ret_from_fork_asm+0x11/0x20
  </TASK>

Weakness: CWE-672 (Operation on a Resource after Expiration or Release)

## Which versions are affected by CVE-2024-49953?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-49953?

Apply the vendor's patch.

## Is CVE-2024-49953 being exploited?

There is no known exploitation of CVE-2024-49953 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-2024-49953 and fix it if it is affected.

What it is: CVE-2024-49953 is a medium-severity use after free vulnerability in Linux kernel, published on 21 Oct 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-2024-49953 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-2024-49953/ (Markdown: https://insights.sbomify.com/CVE-2024-49953/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-49953
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-49953
- OSV: https://osv.dev/vulnerability/CVE-2024-49953

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-49953/
Summaries are generated and may contain mistakes; the official description above is the record.
