CVE-2018-16221

Severity: high (CVSS 8.0 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-05-29 · updated 2026-06-17
Weakness: CWE-22

Description

The diagnostics web interface in the Yeahlink Ultra-elegant IP Phone SIP-T41P (firmware 66.83.0.35) does not validate (escape) the path information (path traversal), which allows an authenticated remote attacker to get access to privileged information (e.g., /etc/passwd) via path traversal (relative path information in the file parameter of the corresponding POST request).

Affected products

Yealink Ultra-Elegant Ip Phone Sip-T41P Firmware: 66.83.0.35

References

https://www.sit.fraunhofer.de/de/securitytestlab/
https://www.sit.fraunhofer.de/fileadmin/dokumente/CVE/Advisory_Yealink_Ultra-elegantIPPhone_SIPT41P.pdf?_=1549375271
https://www.sit.fraunhofer.de/de/securitytestlab/
https://www.sit.fraunhofer.de/fileadmin/dokumente/CVE/Advisory_Yealink_Ultra-elegantIPPhone_SIPT41P.pdf?_=1549375271

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