CVE-2026-46048
In the Linux kernel, the following vulnerability has been resolved: ALSA: caiaq: fix usb_dev refcount leak on probe failure create_card() takes a reference on the USB device with usb_get_dev() and stores the matching usb_put_dev() in card_free(), which is installed as the snd_card's ->private_free destructor. However, ->private_free is only assigned near the end of init_card(), after several failure points (usb_set_interface(), EP type checks, usb_submit_urb(), the EP1_CMD_GET_DEVICE_INFO exchange, and its timeout). When any of those fail, init_card() returns an error to snd_probe(), which calls snd_card_free(card). Because ->private_free is still NULL, card_free() never runs, the usb_get_dev() reference is not dropped, and the struct usb_device leaks along with its descriptor allocations and device_private. syzbot reproduces this with a malformed UAC3 device whose only valid altsetting is 0; init_card()'s usb_set_interface(usb_dev, 0, 1) call fails with -EIO and triggers the leak. Move the ->private_free assignment into create_card(), immediately after usb_get_dev(), so that every error path reaching snd_card_free() balances the reference. card_free()'s callees (snd_usb_caiaq_input_free, free_urbs, kfree) already tolerate the partially-initialized state because the chip private area is zero-initialized by snd_card_new().
Affected versions
Linux kernel versions
6.6.136,
6.12.84,
6.18.25,
7.0.2,
7.1-rc1
and later are affected. Fixed in
6.6.140,
6.12.86,
6.18.27,
7.0.4,
7.1-rc2
and their respective stable series.
References
The following references provide additional information about CVE-2026-46048 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/21ca595aafa40d3ac70eab1f4cb62cc00ca21657
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PatchKernel patch commithttps://git.kernel.org/stable/c/50c6a1f05973f56d23280c9d7645a7a5734e0907
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PatchKernel patch commithttps://git.kernel.org/stable/c/6153878c5255bb69b7d0868105ca078ef13cbcf8
Frequently asked questions
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What is CVE-2026-46048?
CVE-2026-46048 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.6.136 onward and has been patched in 6.6.140, 6.12.86, 6.18.27 and others. CVE-2026-46048 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-46048?
Yes — CVE-2026-46048 has been patched. Fixed versions include 6.6.140, 6.12.86, 6.18.27 and others. If you are running Linux kernel 6.6.136 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-46048 actively exploited?
No — CVE-2026-46048 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.