CVE-2026-46049 ALSA: ctxfi: Add fallback to default RSR for S/PDIF
A logic error in the ALSA ctxfi driver causes an infinite loop during S/PDIF setup, leading to a system hang or denial of service.
- 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-2026-46049?
CVE-2026-46049 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 May 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:
ALSA: ctxfi: Add fallback to default RSR for S/PDIF
spdif_passthru_playback_get_resources() uses atc->pll_rate as the RSR for the MSR calculation loop. However, pll_rate is only updated in atc_pll_init() and not in hw_pll_init(), so it remains 0 after the card init.
When spdif_passthru_playback_setup() skips atc_pll_init() for 32000 Hz, (rsr * desc.msr) always becomes 0, causing the loop to spin indefinitely.
Add fallback to use atc->rsr when atc->pll_rate is 0. This reflects the hardware state, since hw_card_init() already configures the PLL to the default RSR.
Which versions are affected by CVE-2026-46049?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46049?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-46049 being exploited?
There is no known exploitation of CVE-2026-46049 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-88694, BELL-CVE-2026-46049, DEBIAN-CVE-2026-46049, GHSA-cvxr-f657-mx22, ROOT-OS-DEBIAN-11-CVE-2026-46049, ROOT-OS-DEBIAN-12-CVE-2026-46049 and 3 more.