HomeDefectsLIN1023-23565
Fixed

LIN1023-23565 : Security Advisory - linux - CVE-2026-31778

Created: May 12, 2026    Updated: May 14, 2026
Resolved Date: May 12, 2026
Found In Version: 10.23.30.2
Fix Version: 10.23.30.21
Severity: Standard
Applicable for: Wind River Linux LTS 23
Component/s: Kernel

Description

In the Linux kernel, the following vulnerability has been resolved:  ALSA: caiaq: fix stack out-of-bounds read in init_card  The loop creates a whitespace-stripped copy of the card shortname where `len < sizeof(card->id)` is used for the bounds check. Since sizeof(card->id) is 16 and the local id buffer is also 16 bytes, writing 16 non-space characters fills the entire buffer, overwriting the terminating nullbyte.  When this non-null-terminated string is later passed to snd_card_set_id() -> copy_valid_id_string(), the function scans forward with `while (*nid && ...)` and reads past the end of the stack buffer, reading the contents of the stack.  A USB device with a product name containing many non-ASCII, non-space characters (e.g. multibyte UTF-8) will reliably trigger this as follows:    BUG: KASAN: stack-out-of-bounds in copy_valid_id_string        sound/core/init.c:696 [inline]   BUG: KASAN: stack-out-of-bounds in snd_card_set_id_no_lock+0x698/0x74c        sound/core/init.c:718  The off-by-one has been present since commit bafeee5b1f8d ("ALSA: snd_usb_caiaq: give better shortname") from June 2009 (v2.6.31-rc1), which first introduced this whitespace-stripping loop. The original code never accounted for the null terminator when bounding the copy.  Fix this by changing the loop bound to `sizeof(card->id) - 1`, ensuring at least one byte remains as the null terminator.