ISSUE SUMMARY
TTL indexes remove all documents before the current date due to non-numeric types supplied to expiresAfterSeconds being interpreted as 0.

USER IMPACT
Users who supply a non-numeric value to expiresAfterSeconds could have data deleted.

SOLUTION
Mongod will produce an error for TTL indexes created with a non-numeric value for expiresAfterSeconds.

WORKAROUNDS
Users should ensure their application does not pass non-numeric values for expiresAfterSeconds.

PATCHES
Production release v2.4.9 contains the fix for this issue, and production release v2.6.0 will contain the fix as well.