# CVE-2026-12219: Yealink SIP-T46U command injection in Web FastCGI Service

Source: https://junglewise.ai/threats/cve-2026-12219-yealink-sip-t46u-command-injection-in-web-fastcgi-service  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-15. Updated: 2026-06-15  
License: CC BY 4.0 with a link back

CVE-2026-12219 · Severity: medium · CVSS 6.3 · Published 2026-06-15

A security vulnerability has been identified in Yealink SIP-T46U business IP phones. This flaw allows a remote attacker to execute unauthorized commands on the device by manipulating diagnostic settings. If exploited, an attacker could gain control over the phone, potentially leading to unauthorized access to communications or disruption of phone services.

Technologies: [Yealink SIP-T46U](https://junglewise.ai/threats/technologies/sip-t46u). Vendors: [Yealink](https://junglewise.ai/threats/vendors/yealink).

## Quick answers

**Is CVE-2026-12219 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-12219 being exploited in the wild.

**How severe is CVE-2026-12219?** Medium severity, with a CVSS score of 6.3, published 15 June 2026.

**Which products and versions are affected?** Yealink SIP-T46U 108.86.0.118.

**Is there a fix for CVE-2026-12219?** 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-2026-12219 attacked?** It is attacked over the network, in device firmware.

**Am I affected by CVE-2026-12219?** Check whether you run Yealink SIP-T46U 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 command injection vulnerability exists in the Web FastCGI Service of Yealink SIP-T46U firmware version 108.86.0.118. The flaw is located within the mod_diagnose.CommandShellByType function in the /api/diagnosis/start component. An attacker can trigger this vulnerability by providing a specially crafted 'Time' argument, which is improperly neutralized before being passed to a system shell. Exploitation requires network access and low-level authentication (PR:L). Successful exploitation allows for remote code execution on the device. As of the advisory date, the vendor has not provided a patch.

## Affected products

- Yealink SIP-T46U 108.86.0.118

## Timeline

- 2026-06-15: disclosed
- 2026-06-15: advisory: NVD publication date

## References

- [http://cdn2.v50to.cc/T46U/T46U_mod_diagnose_CommandShellByType_iperf_time_cmd_injection.zip](http://cdn2.v50to.cc/T46U/T46U_mod_diagnose_CommandShellByType_iperf_time_cmd_injection.zip)
- [https://vuldb.com/cve/CVE-2026-12219](https://vuldb.com/cve/CVE-2026-12219)
- [https://vuldb.com/submit/834204](https://vuldb.com/submit/834204)
- [https://vuldb.com/vuln/370862](https://vuldb.com/vuln/370862)
- [https://vuldb.com/vuln/370862/cti](https://vuldb.com/vuln/370862/cti)

## Related threats

- [Yealink SIP-T46U command injection in Web FastCGI Service](https://junglewise.ai/threats/cve-2026-12223-yealink-sip-t46u-command-injection-in-web-fastcgi-service)
- [Yealink SIP-T46U stack buffer overflow in Web FastCGI Service](https://junglewise.ai/threats/cve-2026-12222-yealink-sip-t46u-stack-buffer-overflow-in-web-fastcgi-service)
- [Yealink SIP-T46U stack-based buffer overflow in Firmware Chunk Upload Handler](https://junglewise.ai/threats/cve-2026-12221-yealink-sip-t46u-stack-based-buffer-overflow-in-firmware-chunk)
- [Yealink SIP-T46U stack overflow in Firmware Chunk Upload handler](https://junglewise.ai/threats/cve-2026-12220-yealink-sip-t46u-stack-overflow-in-firmware-chunk-upload-handler)
- [Yealink SIP-T46U stack-based buffer overflow in Web FastCGI Service](https://junglewise.ai/threats/cve-2026-12218-yealink-sip-t46u-stack-based-buffer-overflow-in-web-fastcgi)