Microsoft Security Response Center guidance
Vendor revision: Oct 21, 2026Release Notes
Vendor-listed releases
- 6.6.158.1-1
Vulnerability intelligence
CVE-2026-98086. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
Vendor-listed releases
In the Linux kernel, the following vulnerability has been resolved:
ALSA: ump: do not touch legacy_rmidi before it exists
snd_ump_parse_endpoint() sets ump->parsed on every exit, including error, before the caller attaches the legacy rawmidi device. ump_handle_ep_name_msg() then treats parsed as "legacy_rmidi is live" and calls ump_legacy_set_rawmidi_name(), which snprintf()s into ump->legacy_rmidi->name.
If a UMP packet arrives in that window (IRQ path from snd_ump_receive), legacy_rmidi is still NULL (KASAN null-ptr-deref in snprintf).
Guard the legacy helpers. parsed only means endpoint info was parsed, not that legacy_rmidi exists.
Source: NVD