CVE-2026-46172 ipv6: xfrm6: release dst on error in xfrm6_rcv_encap()

What is CVE-2026-46172?

CVE-2026-46172 is a medium-severity denial of service vulnerability in Linux kernel, published on 28 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

ipv6: xfrm6: release dst on error in xfrm6_rcv_encap()

xfrm6_rcv_encap() performs an IPv6 route lookup when the skb does not already have a dst attached. ip6_route_input_lookup() returns a referenced dst entry even when the lookup resolves to an error route.

If dst->error is set, xfrm6_rcv_encap() drops the skb without attaching the dst to the skb and without releasing the reference returned by the lookup. Repeated packets hitting this path therefore leak dst entries.

Release the dst before jumping to the drop path.

Which versions are affected by CVE-2026-46172?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-46172?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-46172 being exploited?

There is no known exploitation of CVE-2026-46172 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-88991, BELL-CVE-2026-46172, DEBIAN-CVE-2026-46172, GHSA-xg6x-xg63-gmxc, ROOT-OS-DEBIAN-11-CVE-2026-46172, ROOT-OS-DEBIAN-12-CVE-2026-46172 and 3 more.