CVE-2026-102761
NetX Duo's WebSocket client resets the unmasking cursor to the first `NX_PACKET` each time it...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
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.
- Record
CVE-2026-102761- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-787
- Updated
- 2026-11-02
EUVDEUVD-2026-89210
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.
- Record
EUVD-2026-89210- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-mjm4-7228-hgjf
NetX Duo's WebSocket client resets the unmasking cursor to the first `NX_PACKET` each time it...
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.
- Record
GHSA-mjm4-7228-hgjf- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-787
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-102761- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2026-102761- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-787
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-102761 is a critical vulnerability (CVSS 9.3) in Eclipse Foundation Netx Duo, published September 29, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.25%, the 16th percentile. No source names a fixed version.