Cyber Resilience

CVE-2023-43959

RCE in Yealink Sip-T19P-E2 Firmware 53.84.0.15

Public PoCRCECommand Injection
Published
17 October 2023
Modified
21 November 2024
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.016 74th percentile
Risk Priority 72 floored blend · peak EPSS

Summary

CVE-2023-43959 is a high-severity OS Command Injection (CWE-78) vulnerability in Yealink Sip-T19P-E2 Firmware. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 26% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2023-43959 affects the Yealink SIP-T19P-E2 VoIP phone running firmware version 53.84.0.15. The flaw resides in the ping function of the device's diagnostic component and stems from improper neutralization of special elements used in an OS command (CWE-78). A remote attacker can supply a crafted request that results in arbitrary code execution on the device.

An attacker with low-privileged network access and no user interaction can exploit the issue to obtain full control over the affected phone. Successful exploitation yields high impact on confidentiality, integrity, and availability, consistent with the CVSS 8.8 rating.

Public proof-of-concept code is available on Exploit-DB and detailed write-ups exist on HackMD, confirming that the vulnerability can be triggered remotely once an attacker reaches the diagnostic interface. The EPSS score has remained flat at 0.0799 with no material increase observed after disclosure.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

An issue in YeaLinkSIP-T19P-E2 v.53.84.0.15 allows a remote privileged attacker to execute arbitrary code via a crafted request the ping function of the diagnostic component.

CWE(s)
CWE-78

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
attack.mitre.org →
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
attack.mitre.org →
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
attack.mitre.org →
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2021-27561Same vendor: Yealink
CVE-2024-24091Same vendor: Yealink
CVE-2024-0292Shared CWE-78
CVE-2023-40479Shared CWE-78
CVE-2025-33206Shared CWE-78
CVE-2026-32608Shared CWE-78
CVE-2024-9916Shared CWE-78
CVE-2026-8665Shared CWE-78
CVE-2026-71950Shared CWE-78
CVE-2024-32123Shared CWE-78

Affected Assets

yealink
sip-t19p-e2 firmware
53.84.0.15

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.5
  • V1.2.8
  • V15.2.5

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SC-27 Platform-independent Applications
addresses: CWE-78

Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.

SI-10 Information Input Validation
addresses: CWE-78

Validates inputs to block special elements that would alter OS command execution.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

References