CVE-2020-28361: kamailio HTTP Request/Response Smuggling

Vulnerability summary

CVE-2020-28361 is a medium (CVSS 5.5) HTTP Request/Response Smuggling vulnerability in kamailio. EPSS estimates a 1.11% chance of exploitation in the next 30 days, higher than 65.3% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 18-11-2020
   PublishedVulnerability first disclosed.
2. 04-08-2024
   Last modifiedVulnerability information updated.

Description

Kamailio before 5.4.0, as used in Sip Express Router (SER) in Sippy Softswitch 4.5 through 5.2 and other products, allows a bypass of a header-removal protection mechanism via whitespace characters. This occurs in the remove_hf function in the Kamailio textops module. Particular use of remove_hf in Sippy Softswitch may allow skilled attacker having a valid credential in the system to disrupt internal call start/duration accounting mechanisms leading potentially to a loss of revenue.

• CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.