PT-2021-5058 · Yealink · Yealink Device Management

Alexandre Torres + 1 · Published 2021-02-23 · Updated 2025-11-10 · CVE-2021-27561

Positive Technologies (AI Summary)

CVSS v2.0

10

Critical

Base vector

AV:N/AC:L/Au:N/C:C/I:C/A:C

Name of the Vulnerable Software and Affected Versions Yealink Device Management version 3.6.0.20

Description The issue is related to a lack of input data sanitization in the Yealink Device Management platform, allowing a remote attacker to execute arbitrary commands as the root user. Specifically, the "/sm/api/v1/firewall/zone/services" API endpoint is vulnerable to command injection without requiring authentication.

Recommendations For Yealink Device Management version 3.6.0.20, consider disabling access to the "/sm/api/v1/firewall/zone/services" API endpoint until a patch is available. Additionally, restrict the use of the firewall/zone/services module to minimize the risk of exploitation. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

OS Command Injection

Command Injection

Weakness Enumeration

CWE-78

CWE-77

Related Identifiers

BDU:2021-05833

CVE-2021-27561

Affected Products

Yealink Device Management

References · 12

• https://nvd.nist.gov/vuln/detail/CVE-2021-27561 · Security Note
• https://bdu.fstec.ru/vul/2021-05833 · Security Note
• https://osv.dev/vulnerability/CVE-2021-27561 · Vendor Advisory
• https://t.me/cybersecuritytechnologies/2791 · Telegram Post
• https://ssd-disclosure.com/?p=4688 · Note
• https://t.me/aptreports/5860 · Telegram Post
• https://t.me/cybersecuritytechnologies/2925 · Telegram Post
• https://t.me/aptreports/5862 · Telegram Post
• https://t.me/cveNotify/142290 · Telegram Post
• https://cisa.gov/known-exploited-vulnerabilities-catalog · Note
• https://cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27561 · Note
• https://t.me/cibsecurity/30663 · Telegram Post