# CVE-2023-53581: net/mlx5e: Check for NOT_READY flag state after locking

> A race condition in the Linux kernel mlx5e driver allows a local attacker to cause a system crash via double-removal from a list.

- **Severity:** Medium 4.7 (`CVSS:3.1/AV:L/AC:H/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:** 4 Oct 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-53581, DEBIAN-CVE-2023-53581, GHSA-r2h4-q9gr-p93h, UBUNTU-CVE-2023-53581

## What is CVE-2023-53581?

CVE-2023-53581 is a medium-severity vulnerability in Linux kernel, published on 4 Oct 2025. 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: Check for NOT_READY flag state after locking

Currently the check for NOT_READY flag is performed before obtaining the
necessary lock. This opens a possibility for race condition when the flow
is concurrently removed from unready_flows list by the workqueue task,
which causes a double-removal from the list and a crash[0]. Fix the issue
by moving the flag check inside the section protected by
uplink_priv->unready_flows_lock mutex.

[0]:
[44376.389654] general protection fault, probably for non-canonical address 0xdead000000000108: 0000 [#1] SMP
[44376.391665] CPU: 7 PID: 59123 Comm: tc Not tainted 6.4.0-rc4+ #1
[44376.392984] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[44376.395342] RIP: 0010:mlx5e_tc_del_fdb_flow+0xb3/0x340 [mlx5_core]
[44376.396857] Code: 00 48 8b b8 68 ce 02 00 e8 8a 4d 02 00 4c 8d a8 a8 01 00 00 4c 89 ef e8 8b 79 88 e1 48 8b 83 98 06 00 00 48 8b 93 90 06 00 00 <48> 89 42 08 48 89 10 48 b8 00 01 00 00 00 00 ad de 48 89 83 90 06
[44376.399167] RSP: 0018:ffff88812cc97570 EFLAGS: 00010246
[44376.399680] RAX: dead000000000122 RBX: ffff8881088e3800 RCX: ffff8881881bac00
[44376.400337] RDX: dead000000000100 RSI: ffff88812cc97500 RDI: ffff8881242f71b0
[44376.401001] RBP: ffff88811cbb0940 R08: 0000000000000400 R09: 0000000000000001
[44376.401663] R10: 0000000000000001 R11: 0000000000000000 R12: ffff88812c944000
[44376.402342] R13: ffff8881242f71a8 R14: ffff8881222b4000 R15: 0000000000000000
[44376.402999] FS:  00007f0451104800(0000) GS:ffff88852cb80000(0000) knlGS:0000000000000000
[44376.403787] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[44376.404343] CR2: 0000000000489108 CR3: 0000000123a79003 CR4: 0000000000370ea0
[44376.405004] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[44376.405665] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[44376.406339] Call Trace:
[44376.406651]  <TASK>
[44376.406939]  ? die_addr+0x33/0x90
[44376.407311]  ? exc_general_protection+0x192/0x390
[44376.407795]  ? asm_exc_general_protection+0x22/0x30
[44376.408292]  ? mlx5e_tc_del_fdb_flow+0xb3/0x340 [mlx5_core]
[44376.408876]  __mlx5e_tc_del_fdb_peer_flow+0xbc/0xe0 [mlx5_core]
[44376.409482]  mlx5e_tc_del_flow+0x42/0x210 [mlx5_core]
[44376.410055]  mlx5e_flow_put+0x25/0x50 [mlx5_core]
[44376.410529]  mlx5e_delete_flower+0x24b/0x350 [mlx5_core]
[44376.411043]  tc_setup_cb_reoffload+0x22/0x80
[44376.411462]  fl_reoffload+0x261/0x2f0 [cls_flower]
[44376.411907]  ? mlx5e_rep_indr_setup_ft_cb+0x160/0x160 [mlx5_core]
[44376.412481]  ? mlx5e_rep_indr_setup_ft_cb+0x160/0x160 [mlx5_core]
[44376.413044]  tcf_block_playback_offloads+0x76/0x170
[44376.413497]  tcf_block_unbind+0x7b/0xd0
[44376.413881]  tcf_block_setup+0x17d/0x1c0
[44376.414269]  tcf_block_offload_cmd.isra.0+0xf1/0x130
[44376.414725]  tcf_block_offload_unbind+0x43/0x70
[44376.415153]  __tcf_block_put+0x82/0x150
[44376.415532]  ingress_destroy+0x22/0x30 [sch_ingress]
[44376.415986]  qdisc_destroy+0x3b/0xd0
[44376.416343]  qdisc_graft+0x4d0/0x620
[44376.416706]  tc_get_qdisc+0x1c9/0x3b0
[44376.417074]  rtnetlink_rcv_msg+0x29c/0x390
[44376.419978]  ? rep_movs_alternative+0x3a/0xa0
[44376.420399]  ? rtnl_calcit.isra.0+0x120/0x120
[44376.420813]  netlink_rcv_skb+0x54/0x100
[44376.421192]  netlink_unicast+0x1f6/0x2c0
[44376.421573]  netlink_sendmsg+0x232/0x4a0
[44376.421980]  sock_sendmsg+0x38/0x60
[44376.422328]  ____sys_sendmsg+0x1d0/0x1e0
[44376.422709]  ? copy_msghdr_from_user+0x6d/0xa0
[44376.423127]  ___sys_sendmsg+0x80/0xc0
[44376.423495]  ? ___sys_recvmsg+0x8b/0xc0
[44376.423869]  __sys_sendmsg+0x51/0x90
[44376.424226]  do_syscall_64+0x3d/0x90
[44376.424587]  entry_SYSCALL_64_after_hwframe+0x46/0xb0
[44376.425046] RIP: 0033:0x7f045134f887
[44376.425403] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00
---truncated---

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2023-53581?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-53581?

Apply the vendor's patch.

## Is CVE-2023-53581 being exploited?

There is no known exploitation of CVE-2023-53581 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-2023-53581 and fix it if it is affected.

What it is: CVE-2023-53581 is a medium-severity vulnerability in Linux kernel, published on 4 Oct 2025. 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-2023-53581 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-2023-53581/ (Markdown: https://insights.sbomify.com/CVE-2023-53581/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53581
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53581
- OSV: https://osv.dev/vulnerability/CVE-2023-53581

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53581/
Summaries are generated and may contain mistakes; the official description above is the record.