while doing cargo build ,error Caused by: [60] SSL peer certificate or SSH remote key was not OK (SSL certificate problem: self signed certificate in certificate chain)

[AiDinho]

Problem

I am new to rust and working through the book .The environment is Ubuntu 16.04.5 LTS on oracle virtual box in windows 7

rustc version -
rustc 1.33.0 (2aa4c46cf 2019-02-28)

cargo version -
cargo 1.33.0 (f099fe9 2019-02-12)

my cargo.toml is like below

[package]
name = "hello_cargo"
version = "0.1.0"
authors = ["biswa"]
edition = "2018"

[dependencies]
rand = "0.3.14"

when I run cargo build I run into this

biswa@biswa-VirtualBox:~/rust_projects/hello_cargo$ cargo build
error: failed to download from `https://crates.io/api/v1/crates/rand/0.3.23/download`

Caused by:
  [60] SSL peer certificate or SSH remote key was not OK (SSL certificate problem: self signed certificate in certificate chain)

I have read here here and here (this one might not be related) that this is due to ssl certificate but I cant seem to fix it .

I have checked strace with cargo fetch but could not figure out which cert.pem its referring to
the pastebin of strace ->https://pastebin.com/74Cjcgp4

FYI I can use pip in this box so its probably not a network issue( in my limited understanding)

Possible Solution(s)

Notes

Output of cargo version: