Free agent Griffiths, 27, has penned a one-year deal at Kenilworth Road, while Wall, 22, has agreed a two-year deal after joining on loan from Maidenhead in March.
Town boss John Still was delighted with the news, as he told the club’s official website: “Both players have shown their quality in the short time they have been with us.
“It’s fantastic for Alex because once we get a pre-season into him he’s going to be one hell of a player.
“He showed that especially in the win over Ebbsfleet when he scored twice.
“As for Scott, he’s experienced, he knows me, and it’s good for him to settle down with a club having led a bit of nomadic career out loan.”
Griffiths, who Still had for six years while at Dagenham & Redbridge, has made six appearances since signing on a short-term deal.
Meanwhile, Wall has played 11 games and opened his goalscoring account with both goals in the 2-0 win over Ebbsfleet recently.
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