CVE-2017-16671 Explained : Impact and Mitigation
Learn about CVE-2017-16671, a Buffer Overflow vulnerability in Asterisk Open Source versions 13, 14, 15, and Certified Asterisk 13. Find out the impact, affected systems, exploitation mechanism, and mitigation steps.
A Buffer Overflow vulnerability was discovered in Asterisk Open Source versions 13 before 13.18.1, 14 before 14.7.1, 15 before 15.1.1, and Certified Asterisk 13.13 before 13.13-cert7. This vulnerability allows an attacker to exploit the user field for Party B in a CDR by using an oversized string, leading to buffer overwrites.
Understanding CVE-2017-16671
This CVE involves a Buffer Overflow vulnerability in Asterisk Open Source versions.
What is CVE-2017-16671?
The vulnerability arises when the user field for Party B in a CDR is set without size checking, enabling attackers to overwrite allocated storage buffers.
The Impact of CVE-2017-16671
- Attackers can exploit the vulnerability by using a string of arbitrary size to overwrite storage buffers.
- This vulnerability is distinct from CVE-2017-7617, which only affected the Party A buffer.
Technical Details of CVE-2017-16671
This section provides technical details of the vulnerability.
Vulnerability Description
- Asterisk Open Source versions are susceptible to a Buffer Overflow issue due to lack of size checking in the user field for Party B in a CDR.
Affected Systems and Versions
- Asterisk Open Source versions 13 before 13.18.1, 14 before 14.7.1, 15 before 15.1.1, and Certified Asterisk 13.13 before 13.13-cert7.
Exploitation Mechanism
- Attackers can exploit the vulnerability by setting the user field for Party B with an oversized string, allowing them to write beyond the allocated storage buffer.
Mitigation and Prevention
Steps to address and prevent the CVE-2017-16671 vulnerability.
Immediate Steps to Take
- Update Asterisk Open Source to versions 13.18.1, 14.7.1, 15.1.1, or Certified Asterisk 13.13-cert7.
- Implement size checking for user fields to prevent buffer overflows.
Long-Term Security Practices
- Regularly monitor and update software to patch known vulnerabilities.
- Conduct security audits to identify and address potential weaknesses.
Patching and Updates
- Apply patches provided by Asterisk to fix the Buffer Overflow vulnerability.