# CVE-2022-49248: ALSA: firewire-lib: fix uninitialized flag for AV/C deferred transaction

> An uninitialized flag in the Linux kernel ALSA firewire driver can cause a UBSAN error and potential system instability during AV/C transactions.

- **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:** 26 Feb 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-49248, GHSA-2583-337f-6vp9, UBUNTU-CVE-2022-49248

## What is CVE-2022-49248?

CVE-2022-49248 is a medium-severity vulnerability in Linux kernel, published on 26 Feb 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:

ALSA: firewire-lib: fix uninitialized flag for AV/C deferred transaction

AV/C deferred transaction was supported at a commit 00a7bb81c20f ("ALSA:
firewire-lib: Add support for deferred transaction") while 'deferrable'
flag can be uninitialized for non-control/notify AV/C transactions.
UBSAN reports it:

kernel: ================================================================================
kernel: UBSAN: invalid-load in /build/linux-aa0B4d/linux-5.15.0/sound/firewire/fcp.c:363:9
kernel: load of value 158 is not a valid value for type '_Bool'
kernel: CPU: 3 PID: 182227 Comm: irq/35-firewire Tainted: P           OE     5.15.0-18-generic #18-Ubuntu
kernel: Hardware name: Gigabyte Technology Co., Ltd. AX370-Gaming 5/AX370-Gaming 5, BIOS F42b 08/01/2019
kernel: Call Trace:
kernel:  <IRQ>
kernel:  show_stack+0x52/0x58
kernel:  dump_stack_lvl+0x4a/0x5f
kernel:  dump_stack+0x10/0x12
kernel:  ubsan_epilogue+0x9/0x45
kernel:  __ubsan_handle_load_invalid_value.cold+0x44/0x49
kernel:  fcp_response.part.0.cold+0x1a/0x2b [snd_firewire_lib]
kernel:  fcp_response+0x28/0x30 [snd_firewire_lib]
kernel:  fw_core_handle_request+0x230/0x3d0 [firewire_core]
kernel:  handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel:  ? handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel:  ? transmit_complete_callback+0x9f/0x120 [firewire_core]
kernel:  ar_context_tasklet+0xa8/0x2e0 [firewire_ohci]
kernel:  tasklet_action_common.constprop.0+0xea/0xf0
kernel:  tasklet_action+0x22/0x30
kernel:  __do_softirq+0xd9/0x2e3
kernel:  ? irq_finalize_oneshot.part.0+0xf0/0xf0
kernel:  do_softirq+0x75/0xa0
kernel:  </IRQ>
kernel:  <TASK>
kernel:  __local_bh_enable_ip+0x50/0x60
kernel:  irq_forced_thread_fn+0x7e/0x90
kernel:  irq_thread+0xba/0x190
kernel:  ? irq_thread_fn+0x60/0x60
kernel:  kthread+0x11e/0x140
kernel:  ? irq_thread_check_affinity+0xf0/0xf0
kernel:  ? set_kthread_struct+0x50/0x50
kernel:  ret_from_fork+0x22/0x30
kernel:  </TASK>
kernel: ================================================================================

This commit fixes the bug. The bug has no disadvantage for the non-
control/notify AV/C transactions since the flag has an effect for AV/C
response with INTERIM (0x0f) status which is not used for the transactions
in AV/C general specification.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2022-49248?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49248?

Apply the vendor's patch.

## Is CVE-2022-49248 being exploited?

There is no known exploitation of CVE-2022-49248 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-2022-49248 and fix it if it is affected.

What it is: CVE-2022-49248 is a medium-severity vulnerability in Linux kernel, published on 26 Feb 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-2022-49248 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-2022-49248/ (Markdown: https://insights.sbomify.com/CVE-2022-49248/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49248
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49248
- OSV: https://osv.dev/vulnerability/CVE-2022-49248

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49248/
Summaries are generated and may contain mistakes; the official description above is the record.