CVE-2026-90086

Published Sep 17, 2026

Description

In the Linux kernel, the following vulnerability has been resolved: xsk: honor XDP_TX_METADATA in zero-copy path The zero-copy path reads TX metadata whenever the UMEM has metadata space, even if the descriptor does not set XDP_TX_METADATA. Pass descriptor options through the metadata helpers and ignore metadata unless the option is set. This does not fix the existing per-WQE metadata handling for mlx5 MPWQEs. Only the descriptor that starts a session passes through xsk_tx_metadata_request() and configures offload state shared by the batch. Metadata on descriptors joining an open session is therefore not validated and does not configure its requested offloads. In addition, a non-NULL metadata pointer from such a descriptor is treated as a timestamp completion request even when XDP_TXMD_FLAGS_TIMESTAMP is not set, so its metadata union can be overwritten with an unrequested timestamp. Fixing mixed metadata states within one MPWQE requires a separate change.

Is your site exposed to CVE-2026-90086?

Run a free security scan — no signup, results in seconds.

References

Frequently Asked Questions

What is CVE-2026-90086? +
In the Linux kernel, the following vulnerability has been resolved: xsk: honor XDP_TX_METADATA in zero-copy path The zero-copy path reads TX metadata whenever the UMEM has metadata space, even if the descriptor does not set XDP_TX_METADATA. Pass descriptor options through the metadata helpers and ignore metadata unless the option is set. This does not fix the existing per-WQE metadata handling for mlx5 MPWQEs. Only the descriptor that starts a session passes through xsk_tx_metadata_request() and configures offload state shared by the batch. Metadata on descriptors joining an open session is therefore not validated and does not configure its requested offloads. In addition, a non-NULL metadata pointer from such a descriptor is treated as a timestamp completion request even when XDP_TXMD_FLAGS_TIMESTAMP is not set, so its metadata union can be overwritten with an unrequested timestamp. Fixing mixed metadata states within one MPWQE requires a separate change.
How do I check if I'm vulnerable to CVE-2026-90086? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-90086 — free, no signup required.