There is some evidence that they have done it becore.
Specifically, that they had a backdoor for Dual EC DRBG[1], and pushed for a shorter key lenghth for DES, to intentionally weaken it.
It is, obviously, controversial. But I think there is certainly enough there that I wouldn't be confident that the NSA wouldn't recommend something they knew to be weak in some way, even to other government organizations.
alt Hacker News
There is some evidence that they have done it becore.
Specifically, that they had a backdoor for Dual EC DRBG[1], and pushed for a shorter key lenghth for DES, to intentionally weaken it.
It is, obviously, controversial. But I think there is certainly enough there that I wouldn't be confident that the NSA wouldn't recommend something they knew to be weak in some way, even to other government organizations.
[1]: https://en.wikipedia.org/wiki/Dual_EC_DRBG