# CVE-2026-55728: Loytec Multiple Products stack overflow in ltsudo

Source: https://junglewise.ai/threats/cve-2026-55728-loytec-multiple-products-stack-overflow-in-ltsudo  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-24. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2026-55728 · Severity: info · CVSS 3.8 · Published 2026-07-24

A security vulnerability exists in several Loytec building automation and control devices, including L-INX and L-GATE servers. An authorized user with high-level administrative access could cause the system to crash or potentially gain even higher system-level privileges by providing an improperly formatted network interface name. This could lead to service disruptions or unauthorized control over the device's operating system.

Technologies: [LOYTEC L-DALI](https://junglewise.ai/threats/technologies/l-dali), [LOYTEC L-GATE](https://junglewise.ai/threats/technologies/l-gate), [LOYTEC L-INX](https://junglewise.ai/threats/technologies/l-inx), [LOYTEC L-IOB](https://junglewise.ai/threats/technologies/l-iob), [LOYTEC L-PAD](https://junglewise.ai/threats/technologies/l-pad), [LOYTEC L-ROC](https://junglewise.ai/threats/technologies/l-roc), [LOYTEC L-VIS](https://junglewise.ai/threats/technologies/l-vis), [LOYTEC LIP-ME201C](https://junglewise.ai/threats/technologies/lip-me201c). Vendors: [LOYTEC](https://junglewise.ai/threats/vendors/loytec).

## Quick answers

**Is CVE-2026-55728 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-55728 being exploited in the wild.

**How severe is CVE-2026-55728?** Informational severity, with a CVSS score of 3.8, published 24 July 2026.

**Which products and versions are affected?** LOYTEC L-DALI through 8.4.16; LOYTEC L-GATE through 8.4.16; LOYTEC L-INX through 8.4.16; LOYTEC L-IOB through 8.4.16; and 4 more.

**Is there a fix for CVE-2026-55728?** A patch was published on 2026-07-24: Fixed in firmware 8.4.18 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-55728 attacked?** It is attacked with local access, in device firmware.

**Am I affected by CVE-2026-55728?** Check whether you run LOYTEC L-DALI, LOYTEC L-GATE, LOYTEC L-INX or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stack-based buffer overflow (CWE-121) exists in the 'cmd_ipaddr_conflict' function within the '/usr/bin/ltsudo' SUID-root binary. The vulnerability is caused by the use of 'strcpy' to copy a user-supplied interface-name argument into a fixed 20-byte stack buffer without length validation. An attacker with 'superadmin' group privileges can exploit this locally to trigger a process abort or potentially achieve arbitrary code execution with root privileges. The issue affects multiple Loytec product lines on the LINX-A64 platform with firmware versions up to 8.4.16. A fix is available in firmware version 8.4.18.

## Affected products

- Loytec LIP-ME201C through 8.4.16
- Loytec L-INX through 8.4.16
- Loytec L-GATE through 8.4.16
- Loytec L-ROC through 8.4.16
- Loytec L-IOB through 8.4.16
- Loytec L-DALI through 8.4.16
- Loytec L-VIS through 8.4.16
- Loytec L-PAD through 8.4.16

## Timeline

- 2026-07-24: advisory
- 2026-07-24: disclosed
- 2026-07-24: patched: Fixed in firmware 8.4.18

## References

- [https://www.loytec.com/support/product-security/advisories/8523-dibt-cve-20260526-0005-stack-buffer-overflow-in-cmd_ipaddr_conflict-low](https://www.loytec.com/support/product-security/advisories/8523-dibt-cve-20260526-0005-stack-buffer-overflow-in-cmd_ipaddr_conflict-low)

## Related threats

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- [Loytec Multiple Products DoS via SNMP Agent CPU Exhaustion](https://junglewise.ai/threats/cve-2026-55731-loytec-multiple-products-dos-via-snmp-agent-cpu-exhaustion)
- [Loytec Building Automation Devices Improper Authentication in PAM](https://junglewise.ai/threats/cve-2026-12504-loytec-building-automation-devices-improper-authentication-in-pam)
- [Loytec Multiple Products privilege escalation in ltsudo](https://junglewise.ai/threats/cve-2026-12502-loytec-multiple-products-privilege-escalation-in-ltsudo)
- [Loytec Multiple Products Stored XSS in OPC XML-DA Server Statistics](https://junglewise.ai/threats/cve-2026-12496-loytec-multiple-products-stored-xss-in-opc-xml-da-server)