PatchSiren

PatchSiren cyber security CVE debrief

CVE-2018-25356 Sipp CVE debrief

A local buffer overflow vulnerability exists in SIPp 3.6 and earlier versions, affecting command-line argument handling. The flaw resides in sipp.cpp where strcpy operations on the -3pcc, -i, and -log_file parameters lack proper bounds checking, allowing oversized input to write beyond allocated buffer boundaries. This vulnerability enables local attackers to crash the application or potentially execute arbitrary code with the privileges of the SIPp process. The attack vector requires local access and user interaction to supply malicious command-line arguments, with no privileges required to trigger the vulnerability. The CVSS 4.0 vector indicates high impacts to confidentiality, integrity, and availability of the vulnerable component.

Vendor
Sipp
Product
Unknown
CVSS
HIGH 8.6
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-23
Original CVE updated
2026-05-26
Advisory published
2026-05-23
Advisory updated
2026-05-26

Who should care

Organizations using SIPp for SIP protocol testing and simulation, particularly those running version 3.6 or earlier in multi-user environments or automated testing pipelines. System administrators responsible for telecommunications infrastructure testing tools. Security teams monitoring for local privilege escalation vectors in network testing applications.

Technical summary

The vulnerability stems from unsafe use of strcpy() in sipp.cpp when processing the -3pcc, -i, and -log_file command-line parameters. Without length validation, attacker-controlled input exceeding buffer boundaries causes memory corruption. This is a classic stack-based buffer overflow (CWE-120) with local attack vector. The CVSS 4.0 score of 8.6 reflects high severity due to potential for arbitrary code execution despite requiring local access. No network attack vector exists; exploitation requires ability to execute SIPp with crafted arguments.

Defensive priority

HIGH

Recommended defensive actions

  • Upgrade SIPp to a version newer than 3.6 where this buffer overflow is addressed
  • Restrict local access to SIPp binaries to authorized administrative users only
  • Implement command-line input validation wrappers that enforce length limits on -3pcc, -i, and -log_file arguments before passing to SIPp
  • Deploy application whitelisting to prevent unauthorized execution of vulnerable SIPp versions
  • Monitor for anomalous process crashes or unexpected code execution originating from SIPp processes
  • Review and update local security policies to prohibit execution of SIPp with untrusted command-line inputs

Evidence notes

Vulnerability confirmed through official CVE record and NVD entry. Advisory from VulnCheck provides technical analysis identifying strcpy as the vulnerable function and specific affected parameters. Exploit-DB reference 44962 documents the issue. CWE-120 (Classic Buffer Overflow) classified as primary weakness. Vendor attribution marked as low confidence requiring review based on reference domain candidate evidence.

Official resources

2026-05-23T19:16:55.900Z