CVE-2026-52981

critical

Description

In the Linux kernel, the following vulnerability has been resolved: neigh: let neigh_xmit take skb ownership neigh_xmit always releases the skb, except when no neighbour table is found. But even the first added user of neigh_xmit (mpls) relied on neigh_xmit to release the skb (or queue it for tx). sashiko reported: If neigh_xmit() is called with an uninitialized neighbor table (for example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT and bypasses its internal out_kfree_skb error path. Because the return value of neigh_xmit() is ignored here, does this leak the SKB? Assume full ownership and remove the last code path that doesn't xmit or free skb.

References

https://git.kernel.org/stable/c/9247d59ca15bf60a57dca08103f055d8a4340877

https://git.kernel.org/stable/c/8a89054a1ec0767aec25ed2bbac933da6ba3cf5a

https://git.kernel.org/stable/c/63063ba60d2dc334e34f1e3f9271d7f3f6f30307

https://git.kernel.org/stable/c/445e45a2c3a078316a62d2d331a570cf34ef5079

https://git.kernel.org/stable/c/4438113be604ee67a7bf4f81da6e1cca41332ce4

https://git.kernel.org/stable/c/0084712e0bee204b284510cdb63182fd5a30c2b7

Details

Source: Mitre, NVD

Published: 2026-06-24

Updated: 2026-06-24

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:C

Severity: High

CVSS v3

Base Score: 9.8

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.00189