Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.(Citation: Wikipedia Man in the Browser)

A specific example is when an adversary injects software into a browser that allows them to inherit cookies, HTTP sessions, and SSL client certificates of a user then use the browser as a way to pivot into an authenticated intranet.(Citation: Cobalt Strike Browser Pivot)(Citation: ICEBRG Chrome Extensions) Executing browser-based behaviors such as pivoting may require specific process permissions, such as <code>SeDebugPrivilege</code> and/or high-integrity/administrator rights.

Another example involves pivoting browser traffic from the adversary's browser through the user's browser by setting up a proxy which will redirect web traffic. This does not alter the user's traffic in any way, and the proxy connection can be severed as soon as the browser is closed. The adversary assumes the security context of whichever browser process the proxy is injected into. Browsers typically create a new process for each tab that is opened and permissions and certificates are separated accordingly. With these permissions, an adversary could potentially browse to any resource on an intranet, such as [Sharepoint](https://attack.mitre.org/techniques/T1213/002) or webmail, that is accessible through the browser and which the browser has sufficient permissions. Browser pivoting may also bypass security provided by 2-factor authentication.(Citation: cobaltstrike manual)
Browser Session Hijacking
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1185  external_id: T1185     source_name: Wikipedia Man in the Browser  description: Wikipedia. (2017, October 28). Man-in-the-browser. Retrieved January 10, 2018.  url: https://en.wikipedia.org/wiki/Man-in-the-browser     source_name: Cobalt Strike Browser Pivot  description: Mudge, R. (n.d.). Browser Pivoting. Retrieved January 10, 2018.  url: https://www.cobaltstrike.com/help-browser-pivoting     source_name: ICEBRG Chrome Extensions  description: De Tore, M., Warner, J. (2018, January 15). MALICIOUS CHROME EXTENSIONS ENABLE CRIMINALS TO IMPACT OVER HALF A MILLION USERS AND GLOBAL BUSINESSES. Retrieved January 17, 2018.  url: https://www.icebrg.io/blog/malicious-chrome-extensions-enable-criminals-to-impact-over-half-a-million-users-and-global-businesses     source_name: cobaltstrike manual  description: Strategic Cyber LLC. (2017, March 14). Cobalt Strike Manual. Retrieved May 24, 2017.  url: https://web.archive.org/web/20210825130434/https://cobaltstrike.com/downloads/csmanual38.pdf     