Vulnerabilities > CVE-2021-36159 - Out-of-bounds Read vulnerability in Freebsd Libfetch

047910
CVSS 9.1 - CRITICAL
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
freebsd
CWE-125
critical

Summary

libfetch before 2021-07-26, as used in apk-tools, xbps, and other products, mishandles numeric strings for the FTP and HTTP protocols. The FTP passive mode implementation allows an out-of-bounds read because strtol is used to parse the relevant numbers into address bytes. It does not check if the line ends prematurely. If it does, the for-loop condition checks for the '\0' terminator one byte too late.

Vulnerable Configurations

Part Description Count
Application
Freebsd
1

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Overread Buffers
    An adversary attacks a target by providing input that causes an application to read beyond the boundary of a defined buffer. This typically occurs when a value influencing where to start or stop reading is set to reflect positions outside of the valid memory location of the buffer. This type of attack may result in exposure of sensitive information, a system crash, or arbitrary code execution.