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.
- 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
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
Which versions are affected by CVE-2026-31585?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-31585?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
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
Sources
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 and 3 more.