How to Fix CVE-2026-31585: media: vidtv: fix nfeeds state corruption on start_streaming failure in Linux
By Sai Kiran Pandrala
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Last verified: 2026-05-25
CVE-2026-31585 is a media: vidtv: fix nfeeds state corruption on start_streaming failure in Linux Linux. Fix it by upgrading to 6.6.136, 6.12.83, 6.18.24, 6.19.14, 7.0.1, 7.1-rc1.
| Severity | Not verified - see official advisory |
|---|---|
| Actively exploited? | Not currently in the CISA KEV catalog |
| Affected | Linux f90cf6079bf67988f8b1ad1ade70fc89d0080905 up to (excluding) 17cb7957c979529cc98ff57f7ac331532f1f7c83; Linux f90cf6079bf67988f8b1ad1ade70fc89d0080905 up to (excluding) 98c22210aeadce67d9d20059f0dbbd01ba7fdbba; Linux f90cf6079bf67988f8b1ad1ade70fc89d0080905 up to (excluding) 25f19e476ab15defe698504212899fdb9f7cd61b; Linux f90cf6079bf67988f8b1ad1ade70fc89d0080905 up to (excluding) 83110c2c8c46c035c2e0fc8ff3e4991183bf9ccd; Linux f90cf6079bf67988f8b1ad1ade70fc89d0080905 up to (excluding) 4bf95f797edd63c93330eafb6d6e670982344b9b; Linux f90cf6079bf67988f8b1ad1ade70fc89d0080905 up to (excluding) a0e5a598fe9a4612b852406b51153b881592aede |
| Fixed in | 6.6.136, 6.12.83, 6.18.24, 6.19.14, 7.0.1, 7.1-rc1 |
| Type (CWE) | Not verified |
What is CVE-2026-31585?
CVE-2026-31585 is a media: vidtv: fix nfeeds state corruption on start_streaming failure flaw in Linux Linux. The vendor has not published a verified CVSS metric at the time of writing. It is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
From the source record: 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.
Why it matters in practice: The blast radius depends on how the affected service is exposed. An internet-facing instance with no compensating controls is the highest-risk configuration.
Am I affected?
You are affected if your installation of Linux matches a version listed in the Affected row above.
# Debian/Ubuntu
dpkg -s linux | grep Version
# RHEL/Rocky
rpm -q linux
How to fix CVE-2026-31585
Apply the vendor patch. Target the build named in the Fixed in row above (6.6.136, 6.12.83, 6.18.24, 6.19.14, 7.0.1, 7.1-rc1). The runnable command set below covers the most common deployment patterns for Linux.
Ubuntu / Debian
sudo apt-get update
sudo apt-get install --only-upgrade linux
dpkg -s linux | grep Version
RHEL / CentOS / Rocky
sudo dnf upgrade linux -y
rpm -q linux
After applying the patch
- Restart the service or device so the patched binary loads.
- Confirm the running version matches the Fixed in row using the verification command below.
- Rotate credentials and API keys that the affected service could access if the asset was exposed during the disclosure window.
If you can't patch immediately
Until the patch lands, narrow the attack surface with these runnable controls.
Restrict network exposure
Block public access to the affected service at the perimeter. Allow only trusted source IPs.
# Linux iptables: only allow trusted admin subnet
sudo iptables -A INPUT -p tcp --dport 443 -s 10.10.10.0/24 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 443 -j DROP
sudo iptables-save | sudo tee /etc/iptables/rules.v4
# Windows firewall: only allow trusted admin subnet on management port
New-NetFirewallRule -DisplayName "Restrict-Mgmt-Allow" -Direction Inbound -Action Allow `
-RemoteAddress 10.10.10.0/24 -Protocol TCP -LocalPort 443
New-NetFirewallRule -DisplayName "Restrict-Mgmt-Deny" -Direction Inbound -Action Block `
-Protocol TCP -LocalPort 443
Mitigations are temporary. Apply the vendor patch as soon as a maintenance window opens.
How to verify the fix worked
Confirm the patched build is the one actually running.
# Debian/Ubuntu
dpkg -s linux | grep Version
# RHEL/Rocky
rpm -q linux
Expected: a version at or above 6.6.136, 6.12.83, 6.18.24, 6.19.14, 7.0.1, 7.1-rc1.
Also worth doing: pull recent log windows for indicators of compromise listed in the vendor advisory, and re-run an authenticated vulnerability scan with up-to-date signatures.
Frequently asked questions
Is CVE-2026-31585 being exploited in the wild?
As of 2026-05-25, CVE-2026-31585 is not listed in the CISA Known Exploited Vulnerabilities catalog. Watch the catalog and patch on a normal cadence; KEV status can change as exploitation evidence emerges.
What is the CVSS score for CVE-2026-31585?
A verified CVSS score is not listed in the public record for CVE-2026-31585. Check the vendor advisory and the NVD page for an updated metric.
What version fixes this?
Upgrade to 6.6.136, 6.12.83, 6.18.24, 6.19.14, 7.0.1, 7.1-rc1.
Will a WAF or IDS rule alone close this?
No. Network filters cut down opportunistic scans but they do not remove the flaw. The vendor patch is the only durable fix.
References
- Official vendor advisory: https://git.kernel.org/stable/c/17cb7957c979529cc98ff57f7ac331532f1f7c83
- NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2026-31585
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- Additional reference: https://git.kernel.org/stable/c/98c22210aeadce67d9d20059f0dbbd01ba7fdbba
- Additional reference: https://git.kernel.org/stable/c/25f19e476ab15defe698504212899fdb9f7cd61b
- Additional reference: https://git.kernel.org/stable/c/83110c2c8c46c035c2e0fc8ff3e4991183bf9ccd
- Additional reference: https://git.kernel.org/stable/c/4bf95f797edd63c93330eafb6d6e670982344b9b
*Assembled from the official vendor advisory, the NVD record, and the CISA KEV listing on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*