CVE-2026-63917
In the Linux kernel, the following vulnerability has been resolved:
ip6: vti: Use ip6_tnl.net in vti6_changelink().
ip netns add ns1
ip netns add ns2
ip -n ns1 link add vti6_test type vti6 remote ::1 local ::2 key 7
ip -n ns1 link set vti6_test netns ns2
ip -n ns2 link set vti6_test type vti6 remote ::3 local ::4 key 9
ip netns del ns2
ip netns del ns1
[ 132.495484] ------------[ cut here ]------------
[ 132.497609] kernel BUG at net/core/dev.c:12376!
Commit 61220ab34948 ("vti6: Enable namespace changing") dropped
NETIF_F_NETNS_LOCAL from vti6 devices. A vti6 tunnel can then
move through IFLA_NET_NS_FD. After the move dev_net(dev) points
at the new netns while t->net stays at the creation netns.
vti6_changelink() and vti6_update() still use dev_net(dev) and
dev_net(t->dev). They unlink from one per netns hash and relink
into another. The creation netns is left with a stale entry.
cleanup_net() of that netns later walks freed memory.
Reachable from an unprivileged user namespace (unshare --user
--map-root-user --net). Cross tenant scope on container hosts.
CSIRTS triage
- What
- Multiple kernel vulnerabilities across architectures and driver subsystems including AMD processor microarchitectural flaws and cache isolation issues.
- Who is affected
- NVIDIA BaseOS systems running affected Linux kernel versions.
- Urgency
- Moderate; privilege escalation and DoS vectors present, primarily requiring local access.
- Action
- Apply USN-8664-1 kernel security update for NVIDIA BaseOS.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch CVE-2026-63917
Get an email if CVE-2026-63917 is added to CISA KEV, gains public exploit code, or a new advisory cites it — max one per day, one-click unsubscribe.
Exploitation outlook
- Low exploitation risk0.17% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all EPSS-scored CVEs.
Advisory coverage (6)
- unknownUSN-8664-1: Linux kernel (NVIDIA BaseOS) vulnerabilitiesubuntu · 2026-08-20
- unknownUSN-8663-1: Linux kernel (NVIDIA) vulnerabilitiesubuntu · 2026-08-20
- highUSN-8618-1: Linux kernel vulnerabilitiesubuntu · 2026-07-28
- highUSN-8603-1: Linux kernel (Azure) vulnerabilitiesubuntu · 2026-07-24
- highUSN-8593-1: Linux kernel vulnerabilitiesubuntu · 2026-07-23
- highCVE-2026-63917: In the Linux kernel, the following vulnerability has been resolved: ip6: vti: Use ip6_tnl.net …nvd · 2026-07-19
External references
Embed the live status
— this badge updates automatically when the KEV or exploit status changes. How to embed it →
[](https://www.csirts.com/cve/CVE-2026-63917)