# CVE-2023-54218: net: Fix load-tearing on sk->sk_stamp in sock_recv_cmsgs().

> A data race in the Linux kernel's socket handling allows local attackers to potentially read inconsistent timestamp data.

- **Severity:** Not scored
- **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:** 30 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-54218, DEBIAN-CVE-2023-54218, GHSA-pjmr-2x65-8v9f, UBUNTU-CVE-2023-54218

## What is CVE-2023-54218?

CVE-2023-54218 is a vulnerability in Linux, published on 30 Dec 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: Fix load-tearing on sk->sk_stamp in sock_recv_cmsgs().

KCSAN found a data race in sock_recv_cmsgs() where the read access
to sk->sk_stamp needs READ_ONCE().

BUG: KCSAN: data-race in packet_recvmsg / packet_recvmsg

write (marked) to 0xffff88803c81f258 of 8 bytes by task 19171 on cpu 0:
 sock_write_timestamp include/net/sock.h:2670 [inline]
 sock_recv_cmsgs include/net/sock.h:2722 [inline]
 packet_recvmsg+0xb97/0xd00 net/packet/af_packet.c:3489
 sock_recvmsg_nosec net/socket.c:1019 [inline]
 sock_recvmsg+0x11a/0x130 net/socket.c:1040
 sock_read_iter+0x176/0x220 net/socket.c:1118
 call_read_iter include/linux/fs.h:1845 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x5e0/0x630 fs/read_write.c:470
 ksys_read+0x163/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x41/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

read to 0xffff88803c81f258 of 8 bytes by task 19183 on cpu 1:
 sock_recv_cmsgs include/net/sock.h:2721 [inline]
 packet_recvmsg+0xb64/0xd00 net/packet/af_packet.c:3489
 sock_recvmsg_nosec net/socket.c:1019 [inline]
 sock_recvmsg+0x11a/0x130 net/socket.c:1040
 sock_read_iter+0x176/0x220 net/socket.c:1118
 call_read_iter include/linux/fs.h:1845 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x5e0/0x630 fs/read_write.c:470
 ksys_read+0x163/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x41/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

value changed: 0xffffffffc4653600 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19183 Comm: syz-executor.5 Not tainted 6.3.0-rc7-02330-gca6270c12e20 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

## Which versions are affected by CVE-2023-54218?


## How do I fix CVE-2023-54218?

Apply the vendor's patch.

## Is CVE-2023-54218 being exploited?

There is no known exploitation of CVE-2023-54218 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54218 and fix it if it is affected.

What it is: CVE-2023-54218 is a vulnerability in Linux, published on 30 Dec 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-2023-54218 in the wild and no public exploit code.

Affected product: Linux. 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-2023-54218/ (Markdown: https://insights.sbomify.com/CVE-2023-54218/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54218
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54218
- OSV: https://osv.dev/vulnerability/CVE-2023-54218

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54218/
Summaries are generated and may contain mistakes; the official description above is the record.