diff --git a/CHANGELOG.md b/CHANGELOG.md
index 89315a1b7..5c860ad67 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,66 @@
 # Changelog
 
+## v0.33.3
+
+*April 6, 2020*
+
+This security release fixes:
+
+### Denial of service 1
+
+Tendermint 0.33.2 and earlier does not limit P2P connection requests number.
+For each p2p connection, Tendermint allocates ~0.5MB. Even though this
+memory is garbage collected once the connection is terminated (due to duplicate
+IP or reaching a maximum number of inbound peers), temporary memory spikes can
+lead to OOM (Out-Of-Memory) exceptions.
+
+Tendermint 0.33.3 (and 0.32.10) limits the total number of P2P incoming
+connection requests to to `p2p.max_num_inbound_peers +
+len(p2p.unconditional_peer_ids)`.
+
+Notes:
+
+- Tendermint does not rate limit P2P connection requests per IP (an attacker
+  can saturate all the inbound slots);
+- Tendermint does not rate limit HTTP(S) requests. If you expose any RPC
+  endpoints to the public, please make sure to put in place some protection
+  (https://www.nginx.com/blog/rate-limiting-nginx/). We may implement this in
+  the future ([\#1696](https://github.com/tendermint/tendermint/issues/1696)).
+
+### Denial of service 2
+
+Tendermint 0.33.2 and earlier does not reclaim `activeID` of a peer after it's
+removed in `Mempool` reactor. This does not happen all the time. It only
+happens when a connection fails (for any reason) before the Peer is created and
+added to all reactors. `RemovePeer` is therefore called before `AddPeer`, which
+leads to always growing memory (`activeIDs` map). The `activeIDs` map has a
+maximum size of 65535 and the node will panic if this map reaches the maximum.
+An attacker can create a lot of connection attempts (exploiting Denial of
+service 1), which ultimately will lead to the node panicking.
+
+Tendermint 0.33.3 (and 0.32.10) claims `activeID` for a peer in `InitPeer`,
+which is executed before `MConnection` is started.
+
+Notes:
+
+- `InitPeer` function was added to all reactors to combat a similar issue -
+  [\#3338](https://github.com/tendermint/tendermint/issues/3338);
+- Denial of service 2 is independent of Denial of service 1 and can be executed
+  without it.
+
+**All clients are recommended to upgrade**
+
+Special thanks to [fudongbai](https://hackerone.com/fudongbai) for finding
+and reporting this.
+
+Friendly reminder, we have a [bug bounty
+program](https://hackerone.com/tendermint).
+
+### SECURITY:
+
+- [mempool] Reserve IDs in InitPeer instead of AddPeer (@tessr)
+- [p2p] Limit the number of incoming connections (@melekes)
+
 ## v0.33.2
 
 *March 11, 2020*
diff --git a/CHANGELOG_PENDING.md b/CHANGELOG_PENDING.md
index 42609c19b..cbda39894 100644
--- a/CHANGELOG_PENDING.md
+++ b/CHANGELOG_PENDING.md
@@ -1,4 +1,4 @@
-## v0.33.3
+## v0.33.4
 
 \*\*
 
diff --git a/version/version.go b/version/version.go
index 9a16e5d58..6e73878c6 100644
--- a/version/version.go
+++ b/version/version.go
@@ -20,7 +20,7 @@ const (
 	// Must be a string because scripts like dist.sh read this file.
 	// XXX: Don't change the name of this variable or you will break
 	// automation :)
-	TMCoreSemVer = "0.33.2"
+	TMCoreSemVer = "0.33.3"
 
 	// ABCISemVer is the semantic version of the ABCI library
 	ABCISemVer  = "0.16.1"