# CVE-2026-10067: Shibby Tomato stack buffer overflow in multimon.cgi

Source: https://junglewise.ai/threats/cve-2026-10067-shibby-tomato-stack-buffer-overflow-in-multimon-cgi  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-29. Updated: 2026-05-29  
License: CC BY 4.0 with a link back

CVE-2026-10067 · Severity: high · CVSS 8.8 · Published 2026-05-29

A vulnerability exists in the Shibby Tomato firmware, which is software used to manage various home and small office routers. The flaw is located in a component used for monitoring Uninterruptible Power Supplies (UPS). If an attacker can control or spoof a UPS device on the network, they can send specially crafted data that crashes the router or potentially allows them to take control of the device. This product is no longer supported, and users are encouraged to migrate to FreshTomato.

Technologies: [Shibby Tomato](https://junglewise.ai/threats/technologies/tomato). Vendors: [Shibby](https://junglewise.ai/threats/vendors/shibby).

## Quick answers

**Is CVE-2026-10067 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-10067 being exploited in the wild.

**How severe is CVE-2026-10067?** High severity, with a CVSS score of 8.8, published 29 May 2026.

**Which products and versions are affected?** Shibby Tomato 1.28.0000 -120 K26ARM USB AIO-64K.

**Is there a fix for CVE-2026-10067?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-10067 attacked?** It is attacked over the network, in device firmware.

**Am I affected by CVE-2026-10067?** Check whether you run Shibby Tomato 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 exists in the sub_90F0 function within multimon.cgi of Shibby Tomato firmware 1.28. The vulnerability is caused by a lack of bounds checking when parsing APC UPS monitoring data. Specifically, the parser uses an unsafe newline-terminated byte-copy loop and an unbounded sscanf() call to write UPS response fields into fixed-size stack buffers (e.g., 0x40 or 0x100 bytes). An attacker who can control or spoof a configured UPS endpoint can return oversized field values (such as DATE or ITEMP) to trigger the overflow. This can lead to memory corruption, process crashes, and potential control-flow hijacking. The issue has been runtime-verified on ARM architecture.

## Affected products

- Shibby Tomato 1.28 1.28.0000 -120 K26ARM USB AIO-64K

## Timeline

- 2026-05-02: disclosed: Initial discovery and report by Fengyi Wang
- 2026-05-29: advisory: CVE published via VulDB/NVD

## References

- [https://gitee.com/Fengyi-Wang/CVE/issues/IJK7BE](https://gitee.com/Fengyi-Wang/CVE/issues/IJK7BE)
- [https://vuldb.com/submit/818146](https://vuldb.com/submit/818146)
- [https://vuldb.com/vuln/367153](https://vuldb.com/vuln/367153)
- [https://vuldb.com/vuln/367153/cti](https://vuldb.com/vuln/367153/cti)

## Related threats

- [Shibby Tomato stack overflow and command injection in Scheduler Name Handler](https://junglewise.ai/threats/cve-2026-16097-shibby-tomato-stack-overflow-and-command-injection-in-scheduler)
- [Shibby Tomato stack overflow in httpd DNS List Rendering](https://junglewise.ai/threats/cve-2026-15548-shibby-tomato-stack-overflow-in-httpd-dns-list-rendering)
- [Shibby Tomato OS command injection in CIFS Mount Handler](https://junglewise.ai/threats/cve-2026-15547-shibby-tomato-os-command-injection-in-cifs-mount-handler)
- [Shibby Tomato OS command injection in rstats_path](https://junglewise.ai/threats/cve-2026-10873-shibby-tomato-os-command-injection-in-rstats-path)
- [Shibby Tomato command injection in start_vpnserver](https://junglewise.ai/threats/cve-2026-10872-shibby-tomato-command-injection-in-start-vpnserver)