White House press secretary Sarah Huckabee Sanders listens to a reporter's question during the daily press briefing at the White House, Tuesday, Dec. 12, 2017, in Washington.
"It all depends on President Trump's volatile mood and available, willing replacements", according to the report.
General McMaster was appointed in February past year following the resignation of Michael Flynn, who has since pleaded guilty to lying to the Federal Bureau of Investigation about his contacts with the Russian government.
John McEntee, Trump's longtime personal aide, was also forced out of the White House on Tuesday after his security clearance was abruptly revoked.
Meanwhile, sources told CBS News that Kelly, who has been known to vex the president from time to time, could also be on the way out of the administration. On Wednesday, he named conservative TV analyst Larry Kudlow to replace his top economic adviser, Gary Cohn, who quit over trade disagreements. "And I think you want to see change", he said.
Several people, including John Bolton, a former US ambassador to the United Nations whom Trump has met several times since assuming office, have been listed by the media as potential candidates for McMaster's job. The conversations included discussions about Obama administration sanctions on Russian Federation for meddling in the 2016 campaign, something Flynn had denied.
Some in the White House have been reluctant to oust McMaster from his national security perch until he has a promotion to four-star rank or other comfortable landing spot, aides said.
General McMaster, whose job requires him to negotiate internal disputes among factions within the administration, as well as deal directly with foreign officials, is operating with the public expectation that every day may be his last.
McMaster is not the only senior official on thin ice with the president. When McMaster arrived, he studied how previous national security advisers had operated and how President Dwight Eisenhower had envisioned the role of the NSC director when he created the White House council. "He asked me to pass that message along to Gen. McMaster".