DEBIAN-CVE-2026-46120

Advisory lineage Upstream: 1 Downstream: 0
Upstream
Published: 28 May 2026, 10:16
Last modified:05 Jul 2026, 20:00

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

28 May 2026, 10:16
Published
Vulnerability first disclosed
05 Jul 2026, 20:00
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: ip6_gre: Use cached t->net in ip6erspan_changelink(). After commit 5e72ce3e3980 ("net: ipv6: Use link netns in newlink() of rtnl_link_ops"), ip6erspan_newlink() correctly resolves the per-netns ip6gre hash via link_net. ip6erspan_changelink() was not converted in that series and still uses dev_net(dev), which diverges from the device's creation netns after IFLA_NET_NS_FD migration. This re-inserts the tunnel into the wrong per-netns hash. The original netns keeps a stale entry. When that netns is later destroyed, ip6gre_exit_rtnl_net() walks the stale entry, producing a slab-use-after-free reported by KASAN, followed by a kernel BUG at net/core/dev.c (LIST_POISON1) in unregister_netdevice_many_notify(). Reachable from an unprivileged user namespace (unshare --user --map-root-user --net). ip6gre_changelink() earlier in the same file already uses the cached t->net; only ip6erspan_changelink() has the wrong shape.

CVSS Metrics

  • v3.1HIGHScore: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • debianlinux

    all | all | < 5.10.259-1 | < 6.1.176-1 | < 6.12.88-1 | < 7.0.7-1

  • debianlinux-6.1

    < 6.1.176-1~deb11u1

References (1)