CVE-2026-102761

NetX Duo's WebSocket client resets the unmasking cursor to the first `NX_PACKET` each time it advances through a chained packet, while the loop's upper bound belongs to the current packet. With the standard contiguous packet-pool layout, a masked server frame split across two packets therefore drives the XOR loop through the first packet's unused payload area and on through the second packet's `NX_PACKET` control block. The four-byte WebSocket masking key controls the bytes written, so the corruption is attacker-chosen rather than incidental.

Score

CVSS 4.0 9.3 Critical

Status

Awaiting Analysis - emo@eclipse.org

Published

2026-09-29

Last modified

2026-09-30

Weaknesses

CWE-787

Affected products

• Netx Duo (Eclipse Foundation)

References

• https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-6xgx-v7gw-qjph