CyberRota Analysis
AI-GeneratedOpenSIPS versions 3.4.0-beta through 3.6.5 and 4.0.0-beta are vulnerable to a critical buffer overflow in the {s.b64encode} string transformation, which can be exploited by remote attackers sending specially crafted SIP messages with large header values. This vulnerability allows attackers to overwrite adjacent memory buffers, potentially leading to arbitrary code execution or denial of service. Organizations using affected versions should prioritize upgrading to versions 3.6.6 or 4.0.0-rc1 to mitigate this risk.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
OpenSIPS is a Session Initiation Protocol (SIP) server implementation. Versions 3.4.0-beta through 3.6.5 and 4.0.0-beta contain a buffer overflow in the {s.b64encode} string transformation. The size check for {s.b64encode} only verifies that the input fits within the 64 KB transformation buffer, but base64 encoding expands the data by roughly a third, so an input between about 49,153 and 65,535 bytes produces more output than the buffer can hold and overflows it by up to 21,844 bytes. Because these transformation buffers sit next to each other in memory and are reused for chained transformations, the overflow writes attacker-controlled data into the adjacent buffer and corrupts values used by later transformations processing the same SIP message. A remote attacker can trigger this by sending a SIP message with a large header value (roughly 50,000 bytes or more) when the routing script applies {s.b64encode} to attacker-controlled input, making exploitability dependent on the deployment's routing configuration. This issue has been fixed in versions 3.6.6 and 4.0.0-rc1.