CVE-2026-52981

CVE-2026-52981 is a high-severity vulnerability with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

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.

Frequently asked questions

What is CVE-2026-52981?
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.
How severe is CVE-2026-52981?
CVE-2026-52981 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-52981 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-52981?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-52981 have an EU (EUVD) identifier?
Yes. CVE-2026-52981 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38849.
When was CVE-2026-52981 published?
CVE-2026-52981 was published on 2026-06-24 and last updated on 2026-06-28.

References