Vulnwatch mailing list archives
Re: [HAT-SQUAD] NetCat Remote Critical Vulnerability, Poc inside.
From: Chris Wysopal <weld () vulnwatch org>
Date: Mon, 27 Dec 2004 20:36:22 -0500 (EST)
Application: Netcat for Windows 1.1 Platform: Windows NT/2000/XP/2003 Severity: Remote code execution Status: Fixed, new version available Date: 12/27/2004 Summary Netcat for Windows 1.1 has a buffer overflow vulnerability that allows remote execution of code. It is exposed when netcat is run using the -e option which execs a process and pipes the listening socket io to the stdio of the exec'd process. Note that this issue does not exist in netcat for the unix platform. Details doexec.c (line 445) was missing a check to see if BufferCnt had incremented past the end of the recieve buffer. With the check in place the buffer is flushed before it overwrites the end. The following new line adds the check. if (RecvBuffer[0] == '\n' || RecvBuffer[0] == '\r' || BufferCnt > BUFFER_SIZE-1) { Update A fixed version, Netcat for Windows 1.11, is available at: http://www.vulnwatch.org/netcat/ Credit Hat Squad discovered this vulnerabiltiy. Hat Squad's advisory is available at http://www.hat-squad.com/en/000142.html
Current thread:
- [HAT-SQUAD] NetCat Remote Critical Vulnerability, Poc inside. class 101 (Dec 27)
- Re: [HAT-SQUAD] NetCat Remote Critical Vulnerability, Poc inside. Chris Wysopal (Dec 27)