Security 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 75th percentile
Risk Priority 72 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

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 NTDS (T1003.003); ranked in the top 25% 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

T1003.003 NTDS Credential Access
Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights.
attack.mitre.org →
T1007 System Service Discovery Discovery
Adversaries may try to gather information about registered local system services.
attack.mitre.org →
T1010 Application Window Discovery Discovery
Adversaries may attempt to get a listing of open application windows.
attack.mitre.org →
T1014 Rootkit Stealth
Adversaries may use rootkits to hide the presence of programs, files, network connections, services, drivers, and other system components.
attack.mitre.org →
T1021.004 SSH Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
attack.mitre.org →
T1021.008 Direct Cloud VM Connections Lateral Movement
Adversaries may leverage [Valid Accounts](https://attack.
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-2023-29120Shared CWE-78
CVE-2017-6398Shared CWE-78
CVE-2023-23777Shared CWE-78
CVE-2024-5403Shared CWE-78
CVE-2025-22606Shared CWE-78
CVE-2021-26747Shared CWE-78
CVE-2026-8985Shared CWE-78
CVE-2026-23699Shared 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

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
blocks

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
blocks

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.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References