The hard-Left leader is thought to be unhappy with the promotion of Lord Goldsmith who laid the groundwork for the legal justification of the Iraq war.
Mr Corbyn based much of his original campaign on his disdain for Tony Blair’s war in Iraq but would have been unable to prevent Lord Goldsmith’s appointment.
Baroness Angela Smith leads Labour in the House of Lords and is responsible for selecting its frontbencher.
It is understood that the move is only temporary and he will not hold the position permanently.
However, he will be in place as the vital Brexit legislation makes its way through the Lords where it is expected to face strong opposition from Europhiles.
The diverging legal advice given by Lord Goldsmith in memos delivered to Prime Minister Blair in January and March 2003 have led to him facing strong criticism.
The party was forced to officially publish the memo in April 2005 after it was leaked.
Lord Goldsmith’s first memo claimed the use of military force against Iraq would not be sanctioned under UN Resolution 1441.
Less than two months later he sent a further memo to Blair which suggested military action could be justified based on Iraq’s “material breach” of its ceasefire obligations.
The Labour Lord wrote: “A reasonable case can be made that resolution 1441 is capable in principle of reviving the authorisation [of the use of force] in Resolution 678 without a further resolution.”
It is understood that due to the temporary nature of the appointment Jeremy Corbyn is prepared to “live with it”.
News of the unexpected appointment comes just after Corbyn attempted to finally start solidifying his party’s Brexit stance.
He said Britain needs a better deal than that of Norway in order to have more influence over UK rule-making.
Corbyn said Labour “wanted to remain and reform but that ship has sailed” as he attempted to outline the party’s view on Brexit.
The Labour leader told BBC’s Andrew Marr the UK must “have influence over the regulations” and develop a “form of customs union”.
But he said the party did not want to remain in the customs union, which would require full membership of the EU.
Mr Corbyn ruled out a Norway style model for Brexit.
He said: “Norway accepts all the rules of the single market, doesn’t have any ability to influence them whatsoever and is a rather different economy to ours because it is heavily dependent on mainly oil. We are not.”
Norway is not a member of the European Union but it is part of the European Economic Area (EEA) and European Free Trade Association (EFTA).
The EEA provides access to the single market in exchange for payments. It also has an “emergency brake” system in place on free movement of people.