Vulnerabilities > CVE-2022-21826 - HTTP Request Smuggling vulnerability in Pulsesecure Pulse Connect Secure

Attack vector
Attack complexity
Privileges required
Confidentiality impact
Integrity impact
Availability impact
low complexity


Pulse Secure version 9.115 and below may be susceptible to client-side http request smuggling, When the application receives a POST request, it ignores the request's Content-Length header and leaves the POST body on the TCP/TLS socket. This body ends up prefixing the next HTTP request sent down that connection, this means when someone loads website attacker may be able to make browser issue a POST to the application, enabling XSS.

Vulnerable Configurations

Part Description Count

Common Attack Pattern Enumeration and Classification (CAPEC)

  • HTTP Request Splitting
    HTTP Request Splitting (also known as HTTP Request Smuggling) is an attack pattern where an attacker attempts to insert additional HTTP requests in the body of the original (enveloping) HTTP request in such a way that the browser interprets it as one request but the web server interprets it as two. There are several ways to perform HTTP request splitting attacks. One way is to include double Content-Length headers in the request to exploit the fact that the devices parsing the request may each use a different header. Another way is to submit an HTTP request with a "Transfer Encoding: chunked" in the request header set with setRequestHeader to allow a payload in the HTTP Request that can be considered as another HTTP Request by a subsequent parsing entity. A third way is to use the "Double CR in an HTTP header" technique. There are also a few less general techniques targeting specific parsing vulnerabilities in certain web servers.
  • HTTP Request Smuggling
    HTTP Request Smuggling results from the discrepancies in parsing HTTP requests between HTTP entities such as web caching proxies or application firewalls. Entities such as web servers, web caching proxies, application firewalls or simple proxies often parse HTTP requests in slightly different ways. Under specific situations where there are two or more such entities in the path of the HTTP request, a specially crafted request is seen by two attacked entities as two different sets of requests. This allows certain requests to be smuggled through to a second entity without the first one realizing it.