ABB IDAL FTP Server Buffer Overflow Vulnerability

17 June 2019

 

IDENTIFIERS  

 

 

CVE-2019-7231

ABBVU-IAMF-1902010

 

CVSS SCORE

 

6.5 (AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

 

XID

 

XL-19-007

 

AFFECTED VENDORS

 

ABB (new.abb.com)

 

CREDIT

 

Eldar Marcussen - xen1thLabs - Software Labs

 

VULNERABILITY SUMMARY       

 

The IDAL FTP server is vulnerable to a buffer overflow where a large string is sent by an authenticated attacker that causes a buffer overflow. This overflow is handled, but terminates the process.

TECHNICAL DETAILS  

 

 

 

An authenticated attacker can send a FTP command string of 472 bytes or more to overflow a buffer causing an exception that terminates the server. An unauthenticated attacker can take advantage of the hardcoded or default credential pair exor/exor to become an authenticated attacker.

 

 PROOF OF CONCEPT

$ perl –e 'print "USER exor\r\nPASS exor\r\n" . "A" x 472 . "\r\n";' | nc targetip 22

 

 

 

Crashing the FTP server.

 

AFFECTED SYSTEMS 

  

PB610 Panel Builder 600, order code: 1SAP500900R0101, versions 1.91 … 2.8.0.367

 

SOLUTION 

 

 

 

 

Apply the patches and instructions from vendor:

- ABB PB610: 

 

DISCLOSURE TIMELINE

 

 

 

 

04/02/2019 - Contacted ABB requesting disclosure coordination

05/02/2019 - Provided vulnerability details

05/06/2019 – Patch available

13/06/2019 – ABB Updated advisory to include this vulnerability

17/06/2019 – xen1thLabs public disclosure