  Here, we revisit the problem of exploring the secrecy capacity of minimum
storage cooperative regenerating (MSCR) codes under the
$\{l_1,l_2\}$-eavesdropper model, where the eavesdropper can observe the data
stored on $l_1$ nodes and the repair downloads of an additional $l_2$ nodes.
Compared to minimum storage regenerating (MSR) codes which support only single
node repairs, MSCR codes allow efficient simultaneous repairs of multiple
failed nodes, referred to as a \emph{repair group}. However, the repair data
sent from a helper node to another failed node may vary with different repair
groups or the sets of helper nodes, which would inevitably leak more data
information to the eavesdropper and even render the storage system unable to
maintain any data secrecy.
  In this paper, we introduce and study a special category of MSCR codes,
termed "\emph{stable}" MSCR codes, where the repair data from any one helper
node to any one failed node is required to be independent of the repair group
or the set of helper nodes. Our main contributions include: 1. Demonstrating
that two existing MSCR codes inherently are not stable and thus have poor
secrecy capacity, 2. Converting one existing MSCR code to a stable one, which
offers better secrecy capacity when compared to the original one, 3. Employing
information theoretic analysis to characterize the secrecy capacity of stable
MSCR codes in certain situations.
