Vulnerability in Linux

CVE-2026-43039

In the Linux kernel, the following vulnerability has been resolved: net: ti: icssg-prueth: fix missing data copy and wrong recycle in ZC RX dispatch emac_dispatch_skb_zc() allocates a new skb via napi_alloc_skb() but never copies the packet data from the XDP buffer into it. The skb is passed up the stack containing uninitialized heap memory instead of the actual received packet, leaking kernel heap contents to userspace. Copy the received packet data from the XDP buffer into the skb using skb_copy_to_linear_data(). Additionally, remove the skb_mark_for_recycle() call since the skb is backed by the NAPI page frag allocator, not page_pool. Marking a non-page_pool skb for recycle causes the free path to return pages to a page_pool that does not own them, corrupting page_pool state. The non-ZC path (emac_rx_packet) does not have these issues because it uses napi_build_skb() to wrap the existing page_pool page directly, requiring no copy, and correctly marks for recycle since the page comes from page_pool_dev_alloc_pages().

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-2026-43039: held from 0.003 to 0.006.

EPSS over last 30 days · oldest: 0.003 · newest: 0.006 · change: +0.002

Affected products

  • Linux — versions 7a64bb388df3cf091afdd047c701039a13acd3b4, 6.19, 0
  • Linux Kernel — versions 7.0

References

Frequently asked questions

What is CVE-2026-43039?
CVE-2026-43039 is a critical-severity vulnerability in Linux. CVSS score: 9.8/10. Published 2026-05-01.
How severe is CVE-2026-43039?
Critical severity. CVSS v3 base score is 9.8 out of 10.