CVE-2026-89736
Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_audio: Fix use-after-free on sound card disconnect g_audio_cleanup() invokes snd_card_free_when_closed() to initiate sound card teardown and immediately frees the underlying struct snd_uac_chip context. However, snd_card_free_when_closed() returns asynchronously while ALSA control elements (kctls) remain open in userspace. When userspace control applications access or close these open file descriptors, kctl callbacks attempt to dereference kctl->private_data pointing to &uac->c_prm or &uac->p_prm within the freed uac structure, resulting in a use-after-free (UAF) memory corruption. Fix this issue by deferring the destruction of struct snd_uac_chip until all references to the ALSA sound card are released. Register a custom card->private_free callback (u_audio_card_free) during g_audio_setup() that frees uac and its associated playback/capture request and ring buffers only when the sound card reference count drops to zero.
How to fix
- Linux Linuxa7ecd1a04f4f485d7be6443d0f0b2c61a800cb82, f983793f03148b097977f200298db215cd2d4438, 6f46762196f04464e1050a9ee94e72b917db9010, 891a8d11f4d5eb50b2ce7570f4f98204a7a57493, c74ff0b1a0fca53d3ac185873c87d6a719b30a47, 4e747c864a88537e18b1ffc19a1954c9686bb8e1, 79a92896e2bb9471550c56fc23d8d93592f04c27, 858965947081d10d41d9a1010a540d3d5eea958b, 5.10.270, 5.15.221, 6.1.188, 4.15, 4.20, 5.5, 6.3 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Linux Linux | 33f341c1fc60e172a3515c51bdabee11e83d1ee9 ≤ v < a7ecd1a04f4f485d7be6443d0f0b2c61a800cb82, b131989797f7287d7fdadb2bababc05a15d44750 ≤ v < f983793f03148b097977f200298db215cd2d4438, 3bc7324e4911351e39c54a62e6ca46321cb10faf ≤ v < 6f46762196f04464e1050a9ee94e72b917db9010, 6c67ed9ad9b83e453e808f9b31a931a20a25629b ≤ v < 891a8d11f4d5eb50b2ce7570f4f98204a7a57493, 6c67ed9ad9b83e453e808f9b31a931a20a25629b ≤ v < c74ff0b1a0fca53d3ac185873c87d6a719b30a47, 6c67ed9ad9b83e453e808f9b31a931a20a25629b ≤ v < 4e747c864a88537e18b1ffc19a1954c9686bb8e1, 6c67ed9ad9b83e453e808f9b31a931a20a25629b ≤ v < 79a92896e2bb9471550c56fc23d8d93592f04c27, 6c67ed9ad9b83e453e808f9b31a931a20a25629b ≤ v < 858965947081d10d41d9a1010a540d3d5eea958b, 3e016ef2e72da93a2ea7afbb45de1b481b44d761, 3256e152b645fc1e788ba44c2d8ced690113e3e6, 0eda2004f38d95ef5715d62be884cd344260535b, 43ca70753dfffd517d2af126da28690f8f615605, 5.10.177 ≤ v < 5.10.270, 5.15.105 ≤ v < 5.15.221, 6.1.22 ≤ v < 6.1.188, 4.14.312 ≤ v < 4.15, 4.19.280 ≤ v < 4.20, 5.4.240 ≤ v < 5.5, 6.2.9 ≤ v < 6.3, 6.3 | a7ecd1a04f4f485d7be6443d0f0b2c61a800cb82, f983793f03148b097977f200298db215cd2d4438, 6f46762196f04464e1050a9ee94e72b917db9010, 891a8d11f4d5eb50b2ce7570f4f98204a7a57493, c74ff0b1a0fca53d3ac185873c87d6a719b30a47, 4e747c864a88537e18b1ffc19a1954c9686bb8e1, 79a92896e2bb9471550c56fc23d8d93592f04c27, 858965947081d10d41d9a1010a540d3d5eea958b, 5.10.270, 5.15.221, 6.1.188, 4.15, 4.20, 5.5, 6.3 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.