Vulnerability in Linux

CVE-2026-72248

In the Linux kernel, the following vulnerability has been resolved: netfilter: flowtable: support IPIP tunnel with direct xmit The combination of IPIP tunnel with direct xmit, eg. bridge device, breaks because no dst_entry is provided to check the skb headroom and to set the iph->frag_off field. This leads to invalid dst usage and can trigger a crash in the tunnel transmit path. Fix this by moving dst_cache and dst_cookie out of the runtime union so that they can be shared by neighbour, xfrm, and direct tunnel flows. For FLOW_OFFLOAD_XMIT_DIRECT tuples carrying tunnel metadata, preserve route state in these shared fields and release it through the common dst release path. Since dst_entry is now available to the three supported xmit modes and dst_release() already deals with NULL dst, remove the xmit type check in nft_flow_dst_release(). Moreover, skip the check if the dst entry is NULL in nf_flow_dst_check() which is now the case for the direct xmit case. Based on patch from Rein Wei <n05ec@lzu.edu.cn>.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (44.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-72248: held from 0.005 to 0.006.

EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.000

Affected products

  • Linux — versions 7.2, 6.19, 7.2-rc3

References

Frequently asked questions

What is CVE-2026-72248?
CVE-2026-72248 is a critical-severity vulnerability in Linux. CVSS score: 9.8/10. Published 2026-08-15.
How severe is CVE-2026-72248?
Critical severity. CVSS v3 base score is 9.8 out of 10.