# CVE-2025-38379: smb: client: fix warning when reconnecting channel
> A null pointer dereference in the Linux kernel SMB client during channel reconnection can cause a system crash.
- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jul 2025
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-65780, BELL-CVE-2025-38379, DEBIAN-CVE-2025-38379, GHSA-mj73-cg42-f79h, UBUNTU-CVE-2025-38379
## What is CVE-2025-38379?
CVE-2025-38379 is a high-severity vulnerability in Linux kernel, published on 25 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
### Official description
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix warning when reconnecting channel
When reconnecting a channel in smb2_reconnect_server(), a dummy tcon
is passed down to smb2_reconnect() with ->query_interface
uninitialized, so we can't call queue_delayed_work() on it.
Fix the following warning by ensuring that we're queueing the delayed
worker from correct tcon.
WARNING: CPU: 4 PID: 1126 at kernel/workqueue.c:2498 __queue_delayed_work+0x1d2/0x200
Modules linked in: cifs cifs_arc4 nls_ucs2_utils cifs_md4 [last unloaded: cifs]
CPU: 4 UID: 0 PID: 1126 Comm: kworker/4:0 Not tainted 6.16.0-rc3 #5 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-4.fc42 04/01/2014
Workqueue: cifsiod smb2_reconnect_server [cifs]
RIP: 0010:__queue_delayed_work+0x1d2/0x200
Code: 41 5e 41 5f e9 7f ee ff ff 90 0f 0b 90 e9 5d ff ff ff bf 02 00
00 00 e8 6c f3 07 00 89 c3 eb bd 90 0f 0b 90 e9 57 f> 0b 90 e9 65 fe
ff ff 90 0f 0b 90 e9 72 fe ff ff 90 0f 0b 90 e9
RSP: 0018:ffffc900014afad8 EFLAGS: 00010003
RAX: 0000000000000000 RBX: ffff888124d99988 RCX: ffffffff81399cc1
RDX: dffffc0000000000 RSI: ffff888114326e00 RDI: ffff888124d999f0
RBP: 000000000000ea60 R08: 0000000000000001 R09: ffffed10249b3331
R10: ffff888124d9998f R11: 0000000000000004 R12: 0000000000000040
R13: ffff888114326e00 R14: ffff888124d999d8 R15: ffff888114939020
FS: 0000000000000000(0000) GS:ffff88829f7fe000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe7a2b4038 CR3: 0000000120a6f000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
queue_delayed_work_on+0xb4/0xc0
smb2_reconnect+0xb22/0xf50 [cifs]
smb2_reconnect_server+0x413/0xd40 [cifs]
? __pfx_smb2_reconnect_server+0x10/0x10 [cifs]
? local_clock_noinstr+0xd/0xd0
? local_clock+0x15/0x30
? lock_release+0x29b/0x390
process_one_work+0x4c5/0xa10
? __pfx_process_one_work+0x10/0x10
? __list_add_valid_or_report+0x37/0x120
worker_thread+0x2f1/0x5a0
? __kthread_parkme+0xde/0x100
? __pfx_worker_thread+0x10/0x10
kthread+0x1fe/0x380
? kthread+0x10f/0x380
? __pfx_kthread+0x10/0x10
? local_clock_noinstr+0xd/0xd0
? ret_from_fork+0x1b/0x1f0
? local_clock+0x15/0x30
? lock_release+0x29b/0x390
? rcu_is_watching+0x20/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork+0x15b/0x1f0
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
irq event stamp: 1116206
hardirqs last enabled at (1116205): [] __up_console_sem+0x52/0x60
hardirqs last disabled at (1116206): [] queue_delayed_work_on+0x6e/0xc0
softirqs last enabled at (1116138): [] __smb_send_rqst+0x42d/0x950 [cifs]
softirqs last disabled at (1116136): [] release_sock+0x21/0xf0
## Which versions are affected by CVE-2025-38379?
It affects 1 product.
Products: Linux kernel.
## How do I fix CVE-2025-38379?
Apply the vendor's patch.
## Is CVE-2025-38379 being exploited?
There is no known exploitation of CVE-2025-38379 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-2025-38379 and fix it if it is affected.
What it is: CVE-2025-38379 is a high-severity vulnerability in Linux kernel, published on 25 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-38379 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-2025-38379/ (Markdown: https://insights.sbomify.com/CVE-2025-38379/index.md)
```
## Sources
- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38379
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38379
- OSV: https://osv.dev/vulnerability/CVE-2025-38379
---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38379/
Summaries are generated and may contain mistakes; the official description above is the record.