Ubuntu has CVE-2026-98432 fixes for 22.04 and newer, but only in -proposed
Ubuntu's status post puts the CVE-2026-98432 kernel fixes in the -proposed pocket for 22.04, 24.04 and 26.04, with 26.10 already fixed in 7.3.0-10.10, 16.04 through 20.04 still pending, and 14.04 listed as not affected. The post also says plainly that mitigations disabling multipath TCP are not the fix, because the flaw is not specific to MPTCP, and it documents the opt-in install path with the warning that -proposed packages are not upgraded by default.