# CVE-2026-31585: media: vidtv: fix nfeeds state corruption on start_streaming failure

> A state corruption bug in the Linux kernel vidtv driver causes memory leaks and potential denial of service when stream initialization fails.

- **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:** 24 Apr 2026
- **Updated:** 14 Jun 2026
- **Also known as:** AZL-84032, BELL-CVE-2026-31585, DEBIAN-CVE-2026-31585, GHSA-vmqh-6ghr-6c6p, ROOT-OS-DEBIAN-11-CVE-2026-31585, ROOT-OS-DEBIAN-12-CVE-2026-31585, ROOT-OS-UBUNTU-2204-CVE-2026-31585, ROOT-OS-UBUNTU-2404-CVE-2026-31585, UBUNTU-CVE-2026-31585

## What is CVE-2026-31585?

CVE-2026-31585 is a medium-severity memory corruption vulnerability in Linux kernel, published on 24 Apr 2026. 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:

media: vidtv: fix nfeeds state corruption on start_streaming failure

syzbot reported a memory leak in vidtv_psi_service_desc_init [1].

When vidtv_start_streaming() fails inside vidtv_start_feed(), the
nfeeds counter is left incremented even though no feed was actually
started. This corrupts the driver state: subsequent start_feed calls
see nfeeds > 1 and skip starting the mux, while stop_feed calls
eventually try to stop a non-existent stream.

This state corruption can also lead to memory leaks, since the mux
and channel resources may be partially allocated during a failed
start_streaming but never cleaned up, as the stop path finds
dvb->streaming == false and returns early.

Fix by decrementing nfeeds back when start_streaming fails, keeping
the counter in sync with the actual number of active feeds.

[1]
BUG: memory leak
unreferenced object 0xffff888145b50820 (size 32):
 comm "syz.0.17", pid 6068, jiffies 4294944486
 backtrace (crc 90a0c7d4):
  vidtv_psi_service_desc_init+0x74/0x1b0 drivers/media/test-drivers/vidtv/vidtv_psi.c:288
  vidtv_channel_s302m_init+0xb1/0x2a0 drivers/media/test-drivers/vidtv/vidtv_channel.c:83
  vidtv_channels_init+0x1b/0x40 drivers/media/test-drivers/vidtv/vidtv_channel.c:524
  vidtv_mux_init+0x516/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:518
  vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline]
  vidtv_start_feed+0x33e/0x4d0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2026-31585?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-31585?

Apply the vendor's patch.

## Is CVE-2026-31585 being exploited?

There is no known exploitation of CVE-2026-31585 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-2026-31585 and fix it if it is affected.

What it is: CVE-2026-31585 is a medium-severity memory corruption vulnerability in Linux kernel, published on 24 Apr 2026. 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-2026-31585 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-2026-31585/ (Markdown: https://insights.sbomify.com/CVE-2026-31585/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31585
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31585
- OSV: https://osv.dev/vulnerability/CVE-2026-31585

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31585/
Summaries are generated and may contain mistakes; the official description above is the record.
