CVE-2026-97597

NameCVE-2026-97597
DescriptionIn the Linux kernel, the following vulnerability has been resolved: ipv6: flowlabel: cap duplicate leases per socket ipv6_flowlabel_get() allocates an ipv6_fl_socklist entry for every successful GET. The recheck path for a compatible existing flowlabel links another lease without applying any lease admission check. Repeated GET requests for one shareable label can therefore grow a socket's lease list without bound. Reject a new unprivileged lease once the socket already holds FL_MAX_PER_SOCK leases. Check this on the shared recheck path so reuse of a globally interned label, including the fl_intern() collision path, is covered as well. New-label admission remains under the existing mem_check() policy. Use capable(CAP_NET_ADMIN) rather than ns_capable(), matching mem_check(). An unprivileged user must not bypass the cap by creating a user namespace and a netns where they have CAP_NET_ADMIN, which would still consume host memory. Check the capability only when the socket reaches the limit, so successful unprivileged GET requests below the cap do not generate a capability audit. Do the admission check before updating linger and expires so a rejected GET does not refresh the shared label, matching the existing socket-list allocation failure path.
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
linux (PTS)bookworm6.1.176-1vulnerable
bookworm (security)6.1.187-1vulnerable
trixie6.12.107-1vulnerable
trixie (security)6.12.111-1vulnerable
forky7.2.9-1fixed
sid7.2.10-1fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
linuxsource(unstable)7.2.7-1

Notes

https://git.kernel.org/linus/8d6cd188508513503805c156165de38e4e4a8615 (7.3-rc3)

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