diff --git a/include/znc/ZNCDebug.h b/include/znc/ZNCDebug.h
index 8a82027b..d81fe93c 100644
--- a/include/znc/ZNCDebug.h
+++ b/include/znc/ZNCDebug.h
@@ -47,6 +47,8 @@ class CDebug {
     static void SetDebug(bool b) { debug = b; }
     static bool Debug() { return debug; }
 
+    static CString Filter(const CString& sUnfilteredLine);
+
   protected:
     static bool stdoutIsTTY;
     static bool debug;
diff --git a/src/Client.cpp b/src/Client.cpp
index 11626bf9..745a4173 100644
--- a/src/Client.cpp
+++ b/src/Client.cpp
@@ -20,6 +20,7 @@
 #include <znc/User.h>
 #include <znc/IRCNetwork.h>
 #include <znc/Query.h>
+#include <znc/ZNCDebug.h>
 
 using std::set;
 using std::map;
@@ -105,7 +106,8 @@ void CClient::ReadLine(const CString& sData) {
 
     sLine.TrimRight("\n\r");
 
-    DEBUG("(" << GetFullName() << ") CLI -> ZNC [" << sLine << "]");
+    DEBUG("(" << GetFullName() << ") CLI -> ZNC ["
+        << CDebug::Filter(sLine) << "]");
 
     MCString mssTags;
     if (sLine.StartsWith("@")) {
@@ -586,7 +588,8 @@ bool CClient::PutClient(const CMessage& Message) {
                       &bReturn);
     if (bReturn) return false;
 
-    DEBUG("(" << GetFullName() << ") ZNC -> CLI [" << sCopy << "]");
+    DEBUG("(" << GetFullName() << ") ZNC -> CLI ["
+        << CDebug::Filter(sCopy) << "]");
     Write(sCopy + "\r\n");
     return true;
 }
diff --git a/src/IRCSock.cpp b/src/IRCSock.cpp
index a0c5a07f..09cfbb9f 100644
--- a/src/IRCSock.cpp
+++ b/src/IRCSock.cpp
@@ -20,6 +20,7 @@
 #include <znc/IRCNetwork.h>
 #include <znc/Server.h>
 #include <znc/Query.h>
+#include <znc/ZNCDebug.h>
 #include <time.h>
 
 using std::set;
@@ -1128,8 +1129,8 @@ void CIRCSock::PutIRC(const CString& sLine) {
     // TrySend()!)
     if (m_bFloodProtection && m_iSendsAllowed <= 0) {
         DEBUG("(" << m_pNetwork->GetUser()->GetUserName() << "/"
-                  << m_pNetwork->GetName() << ") ZNC -> IRC [" << sLine
-                  << "] (queued)");
+                  << m_pNetwork->GetName() << ") ZNC -> IRC ["
+                  << CDebug::Filter(sLine) << "] (queued)");
     }
     m_vsSendQueue.push_back(sLine);
     TrySend();
@@ -1140,8 +1141,8 @@ void CIRCSock::PutIRCQuick(const CString& sLine) {
     // TrySend()!)
     if (m_bFloodProtection && m_iSendsAllowed <= 0) {
         DEBUG("(" << m_pNetwork->GetUser()->GetUserName() << "/"
-                  << m_pNetwork->GetName() << ") ZNC -> IRC [" << sLine
-                  << "] (queued to front)");
+                  << m_pNetwork->GetName() << ") ZNC -> IRC ["
+                  << CDebug::Filter(sLine) << "] (queued to front)");
     }
     m_vsSendQueue.push_front(sLine);
     TrySend();
@@ -1164,8 +1165,8 @@ void CIRCSock::TrySend() {
             IRCSOCKMODULECALL(OnSendToIRC(sCopy), &bSkip);
             if (!bSkip) {
                 DEBUG("(" << m_pNetwork->GetUser()->GetUserName() << "/"
-                        << m_pNetwork->GetName() << ") ZNC -> IRC [" << sCopy
-                        << "]");
+                        << m_pNetwork->GetName() << ") ZNC -> IRC ["
+                        << CDebug::Filter(sCopy) << "]");
                 Write(sCopy + "\r\n");
             }
         }
diff --git a/src/ZNCDebug.cpp b/src/ZNCDebug.cpp
index 2b883eff..775c1f31 100644
--- a/src/ZNCDebug.cpp
+++ b/src/ZNCDebug.cpp
@@ -29,6 +29,22 @@ bool CDebug::debug =
     false;
 #endif
 
+CString CDebug::Filter(const CString& sUnfilteredLine) {
+    CString sFilteredLine = sUnfilteredLine;
+
+    // If the line is a PASS command to authenticate to a server / znc
+    if (sUnfilteredLine.StartsWith("PASS ")) {
+        VCString vsSafeCopy;
+        sUnfilteredLine.Split(":", vsSafeCopy);
+
+        if (vsSafeCopy.size() > 1) {
+            sFilteredLine = vsSafeCopy[0] + ":<censored>";
+        }
+    }
+
+    return sFilteredLine;
+}
+
 CDebugStream::~CDebugStream() {
     timeval tTime = CUtils::GetTime();
     time_t tSec = (time_t)tTime.tv_sec;  // some systems (e.g. openbsd) define