cbcvebase.
CVE-2019-17662
published 2019-10-16

CVE-2019-17662: ThinVNC 1.0b1 is vulnerable to arbitrary file read, which leads to a compromise of the VNC server. The vulnerability exists even when authentication is turned…

PriorityP182critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EXPLOIT
EPSS
96.76%
99.9th percentile
ThinVNC 1.0b1 is vulnerable to arbitrary file read, which leads to a compromise of the VNC server. The vulnerability exists even when authentication is turned on during the deployment of the VNC server. The password for authentication is stored in cleartext in a file that can be read via a ../../ThinVnc.ini directory traversal attack vector.

Affected

1 ranges
VendorProductVersion rangeFixed in
cybelsoftthinvnc

Detection & IOCsextracted from sources · hover to see the quote

path/xyz/../../ThinVnc.ini
path/{{randstr}}/../../ThinVnc.ini
filenameThinVnc.ini
otherhttp.favicon.hash:-1414548363
othericon_hash=-1414548363
  • HTTP response body contains both 'User=' and 'Password=' strings, indicating successful ThinVnc.ini file read via directory traversal.
  • HTTP response Content-Type header contains 'application/binary' when ThinVnc.ini is successfully retrieved.
  • HTTP GET request to a path containing '../../ThinVnc.ini' is the canonical exploit pattern for this CVE; monitor web server logs for this traversal sequence.
  • The vulnerability is exploitable even when authentication is enabled; unauthenticated HTTP GET requests to the traversal path should be alerted on regardless of auth state.
  • ·The vulnerability affects ThinVNC 1.0b1 and prior, including the 'ThinVNC_Latest' build dated 2018-12-07; scope detection rules accordingly.
  • ·Credentials (username and password) are stored in cleartext inside ThinVnc.ini; if the file is read, full authentication bypass is achieved without any further exploitation.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:N
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