@@ -52,8 +52,14 @@ fi
 echo ""
 echo "Generating SQL Server password..."
 SA_PASSWORD="$(openssl rand -base64 16 | tr -dc 'A-Za-z0-9' | head -c 16)Aa1!"
-echo "$SA_PASSWORD" > /tmp/.sqlserver_sa_password
-chmod 600 /tmp/.sqlserver_sa_password
+# mktemp creates 0600; chmod before writing keeps it owner-only without touching the global umask.
+SQL_ENV_FILE="$(mktemp)"
+chmod 600 "$SQL_ENV_FILE"
+trap 'rm -f "$SQL_ENV_FILE"' EXIT
+trap 'exit 129' HUP
+trap 'exit 130' INT
+trap 'exit 143' TERM
+printf 'ACCEPT_EULA=Y\nMSSQL_SA_PASSWORD=%s\n' "$SA_PASSWORD" > "$SQL_ENV_FILE"
 
 # Start SQL Server container (use Azure SQL Edge for ARM64 compatibility)
 # This is optional - if Docker-in-Docker fails, the devcontainer still works
@@ -63,15 +69,17 @@ echo "Starting SQL Server container (optional)..."
 ARCH=$(uname -m)
 if [[ "$ARCH" == "aarch64" || "$ARCH" == "arm64" ]]; then
     echo "Detected ARM64 - using Azure SQL Edge..."
-    docker run -e 'ACCEPT_EULA=Y' -e "MSSQL_SA_PASSWORD=$SA_PASSWORD" \
+    docker run --env-file "$SQL_ENV_FILE" \
         -p 1433:1433 --name sqlserver \
         -d mcr.microsoft.com/azure-sql-edge:latest && SQL_STARTED=true || SQL_STARTED=false
 else
     echo "Detected x86_64 - using SQL Server 2025..."
-    docker run -e 'ACCEPT_EULA=Y' -e "MSSQL_SA_PASSWORD=$SA_PASSWORD" \
+    docker run --env-file "$SQL_ENV_FILE" \
         -p 1433:1433 --name sqlserver \
         -d mcr.microsoft.com/mssql/server:2025-latest && SQL_STARTED=true || SQL_STARTED=false
 fi
+rm -f "$SQL_ENV_FILE"
+trap - EXIT HUP INT TERM
 
 if [ "$SQL_STARTED" = "true" ]; then
     echo "Waiting for SQL Server to start..."
@@ -85,12 +93,18 @@ fi
 # Set DB_CONNECTION_STRING environment variable (persist across all terminals)
 DB_CONNECTION_STRING="Server=localhost,1433;Database=master;UID=sa;PWD=$SA_PASSWORD;TrustServerCertificate=Yes;Encrypt=Yes"
 
-# Write to /etc/environment for system-wide persistence
-echo "DB_CONNECTION_STRING=\"$DB_CONNECTION_STRING\"" | sudo tee -a /etc/environment > /dev/null
-
-# Also add to shell rc files for immediate availability in new terminals
-echo "export DB_CONNECTION_STRING=\"$DB_CONNECTION_STRING\"" >> ~/.bashrc
-echo "export DB_CONNECTION_STRING=\"$DB_CONNECTION_STRING\"" >> ~/.zshrc
+# Keep the credential in a user-only file and source it from interactive shells.
+MSSQL_ENV_FILE="$HOME/.mssql_python_env"
+# Scope umask to this write only so the file is owner-only from creation; global umask stays untouched.
+( umask 077; touch "$MSSQL_ENV_FILE"; chmod 600 "$MSSQL_ENV_FILE"; printf "export DB_CONNECTION_STRING='%s'\n" "$DB_CONNECTION_STRING" > "$MSSQL_ENV_FILE" )
+
+# Remove plaintext entries left by older versions of this script.
+[ -f /etc/environment ] && sudo sed -i '/^DB_CONNECTION_STRING=/d' /etc/environment
+[ -f ~/.bashrc ] && sed -i '/^export DB_CONNECTION_STRING=/d' ~/.bashrc
+[ -f ~/.zshrc ] && sed -i '/^export DB_CONNECTION_STRING=/d' ~/.zshrc
+rm -f /tmp/.sqlserver_sa_password
+grep -qxF 'source ~/.mssql_python_env' ~/.bashrc 2>/dev/null || echo 'source ~/.mssql_python_env' >> ~/.bashrc
+grep -qxF 'source ~/.mssql_python_env' ~/.zshrc 2>/dev/null || echo 'source ~/.mssql_python_env' >> ~/.zshrc
 
 # Export for current session
 export DB_CONNECTION_STRING
 
@@ -136,7 +136,7 @@ stages:
             displayName: 'Start $(LINUX_TAG) $(ARCH) container'
           
           - script: |
-              set -euxo pipefail
+              set -euo pipefail
               export PATH=$PATH:`pwd`/docker
               CONTAINER="build-$(LINUX_TAG)-$(ARCH)"
 
@@ -170,7 +170,7 @@ stages:
               # manager is flaky under emulation (the header gate below is the real check).
               if [[ "$(LINUX_TAG)" == "manylinux_2_28" ]]; then
                 docker exec "$CONTAINER" bash -lc '
-                  set -uxo pipefail
+                  set -uo pipefail
                   if command -v dnf >/dev/null 2>&1; then
                     dnf -y install gcc gcc-c++ make cmake unixODBC-devel krb5-libs keyutils-libs ccache curl || true
                   elif command -v yum >/dev/null 2>&1; then
@@ -181,7 +181,7 @@ stages:
                 '
               else
                 docker exec "$CONTAINER" sh -lc '
-                  set -uxo pipefail
+                  set -uo pipefail
                   apk add --no-cache bash build-base cmake unixodbc-dev krb5-libs keyutils-libs ccache curl || true
                   gcc --version || true
                   cmake --version || true
@@ -199,20 +199,20 @@ stages:
           # Start SQL Server container for pytest execution
           # Runs on host (not in build container) to be accessible from build container via network
           - script: |
-              set -euxo pipefail
+              set -euo pipefail
               
               echo "Starting SQL Server 2022 container for testing..."
               docker run -d --name sqlserver-$(LINUX_TAG)-$(ARCH) \
                 --platform linux/amd64 \
                 -e ACCEPT_EULA=Y \
-                -e MSSQL_SA_PASSWORD="$(DB_PASSWORD)" \
+                -e MSSQL_SA_PASSWORD \
                 -p 1433:1433 \
                 mcr.microsoft.com/mssql/server:2022-latest
               
               echo "Waiting for SQL Server to be ready..."
               for i in {1..30}; do
-                if docker exec sqlserver-$(LINUX_TAG)-$(ARCH) /opt/mssql-tools18/bin/sqlcmd \
-                  -S localhost -U SA -P "$(DB_PASSWORD)" -C -Q "SELECT 1" >/dev/null 2>&1; then
+                if docker exec -e SQLCMDPASSWORD sqlserver-$(LINUX_TAG)-$(ARCH) /opt/mssql-tools18/bin/sqlcmd \
+                  -S localhost -U SA -C -Q "SELECT 1" >/dev/null 2>&1; then
                   echo "✓ SQL Server is ready!"
                   break
                 fi
@@ -226,6 +226,8 @@ stages:
             displayName: 'Start SQL Server container for testing'
             env:
               DB_PASSWORD: $(DB_PASSWORD)
+              MSSQL_SA_PASSWORD: $(DB_PASSWORD)
+              SQLCMDPASSWORD: $(DB_PASSWORD)
           
           # =========================
           # PHASE 2: EXTERNAL ODBC DRIVER PACKAGE
@@ -256,7 +258,7 @@ stages:
           
           # Build wheels for all Python versions (3.10-3.14) and test each one
           - script: |
-              set -euxo pipefail
+              set -euo pipefail
               if [[ "$(LINUX_TAG)" == "manylinux_2_28" ]]; then SHELL_EXE=bash; else SHELL_EXE=sh; fi
               docker exec build-$(LINUX_TAG)-$(ARCH) $SHELL_EXE -lc 'mkdir -p /workspace/dist'
               
@@ -269,8 +271,8 @@ stages:
                 
                 if [[ "$(LINUX_TAG)" == "manylinux_2_28" ]]; then
                   # Manylinux (glibc-based) - use bash
-                  docker exec -e PYBIN=$PYBIN -e SQL_IP=$(SQL_IP) -e DB_PASSWORD="$(DB_PASSWORD)" -e MANYLINUX_TAG="$(LINUX_TAG)" -e PIP_FIND_LINKS="/workspace/odbc_wheels" build-$(LINUX_TAG)-$(ARCH) bash -lc '
-                    set -euxo pipefail;
+                  docker exec -e PYBIN=$PYBIN -e SQL_IP=$(SQL_IP) -e DB_PASSWORD -e MANYLINUX_TAG="$(LINUX_TAG)" -e PIP_FIND_LINKS="/workspace/odbc_wheels" build-$(LINUX_TAG)-$(ARCH) bash -lc '
+                    set -euo pipefail;
                     
                     # Step 1: Setup Python environment
                     PY=/opt/python/${PYBIN}-${PYBIN}/bin/python;
@@ -339,8 +341,8 @@ stages:
                   '
                 else
                   # Musllinux (musl libc-based) - use sh
-                  docker exec -e PYBIN=$PYBIN -e SQL_IP=$(SQL_IP) -e DB_PASSWORD="$(DB_PASSWORD)" -e MANYLINUX_TAG="$(LINUX_TAG)" -e PIP_FIND_LINKS="/workspace/odbc_wheels" build-$(LINUX_TAG)-$(ARCH) sh -lc '
-                    set -euxo pipefail;
+                  docker exec -e PYBIN=$PYBIN -e SQL_IP=$(SQL_IP) -e DB_PASSWORD -e MANYLINUX_TAG="$(LINUX_TAG)" -e PIP_FIND_LINKS="/workspace/odbc_wheels" build-$(LINUX_TAG)-$(ARCH) sh -lc '
+                    set -euo pipefail;
                     
                     # Step 1: Setup Python environment
                     PY=/opt/python/${PYBIN}-${PYBIN}/bin/python;
@@ -422,7 +424,7 @@ stages:
           
           # Copy built artifacts from container to host for publishing
           - script: |
-              set -euxo pipefail
+              set -euo pipefail
               
               # Copy all wheels (5 Python versions) to output directory
               echo "Copying wheels to host..."
 
@@ -161,20 +161,22 @@ stages:
               docker pull mcr.microsoft.com/mssql/server:2022-latest
               docker run --name sqlserver \
                 -e ACCEPT_EULA=Y \
-                -e MSSQL_SA_PASSWORD="${DB_PASSWORD}" \
+                -e MSSQL_SA_PASSWORD \
                 -p 1433:1433 -d \
                 mcr.microsoft.com/mssql/server:2022-latest
               
               # Wait for SQL Server to accept connections (up to 60 seconds)
               # sqlcmd -C flag = trust server certificate (for TLS connection)
               for i in {1..30}; do
-                docker exec sqlserver /opt/mssql-tools18/bin/sqlcmd \
-                  -S localhost -U SA -P "$DB_PASSWORD" -C -Q "SELECT 1" && break
+                docker exec -e SQLCMDPASSWORD sqlserver /opt/mssql-tools18/bin/sqlcmd \
+                  -S localhost -U SA -C -Q "SELECT 1" && break
                 sleep 2
               done
             displayName: 'Start SQL Server (Docker)'
             env:
               DB_PASSWORD: $(DB_PASSWORD)
+              MSSQL_SA_PASSWORD: $(DB_PASSWORD)
+              SQLCMDPASSWORD: $(DB_PASSWORD)
           
           # =========================
           # MSSQL-PYTHON-RS INSTALLATION
 
@@ -168,7 +168,20 @@ stages:
           
           - powershell: |
               sqlcmd -S "(localdb)\MSSQLLocalDB" -Q "CREATE DATABASE TestDB"
-              sqlcmd -S "(localdb)\MSSQLLocalDB" -Q "CREATE LOGIN testuser WITH PASSWORD = '$(DB_PASSWORD)'"
+              $sqlPassword = $env:DB_PASSWORD.Replace("'", "''")
+              $sqlPath = Join-Path $env:TEMP ("create-testuser-{0}.sql" -f [guid]::NewGuid())
+              $sqlBytes = (New-Object System.Text.UTF8Encoding($false)).GetBytes("CREATE LOGIN testuser WITH PASSWORD = '$sqlPassword'`n")
+              [System.IO.File]::Create($sqlPath).Dispose()
+              try {
+                $identity = [System.Security.Principal.WindowsIdentity]::GetCurrent().Name
+                icacls $sqlPath /inheritance:r /grant:r "${identity}:(F)" "SYSTEM:(R)" | Out-Null
+                if ($LASTEXITCODE -ne 0) { throw "Failed to secure temporary SQL file" }
+                [System.IO.File]::WriteAllBytes($sqlPath, $sqlBytes)
+                sqlcmd -S "(localdb)\MSSQLLocalDB" -i $sqlPath -b -x -f 65001
+                if ($LASTEXITCODE -ne 0) { throw "Failed to create the testuser login" }
+              } finally {
+                Remove-Item $sqlPath -Force -ErrorAction Stop
+              }
               sqlcmd -S "(localdb)\MSSQLLocalDB" -d TestDB -Q "CREATE USER testuser FOR LOGIN testuser"
               sqlcmd -S "(localdb)\MSSQLLocalDB" -d TestDB -Q "ALTER ROLE db_owner ADD MEMBER testuser"
             displayName: 'Setup database and user'
 
@@ -107,7 +107,20 @@ jobs:
   - powershell: |
       Write-Host "Creating database and user for stress tests..."
       sqlcmd -S "(localdb)\MSSQLLocalDB" -Q "CREATE DATABASE StressTestDB"
-      sqlcmd -S "(localdb)\MSSQLLocalDB" -Q "CREATE LOGIN testuser WITH PASSWORD = '$env:DB_PASSWORD'"
+      $sqlPassword = $env:DB_PASSWORD.Replace("'", "''")
+      $sqlPath = Join-Path $env:TEMP ("create-testuser-{0}.sql" -f [guid]::NewGuid())
+      $sqlBytes = (New-Object System.Text.UTF8Encoding($false)).GetBytes("CREATE LOGIN testuser WITH PASSWORD = '$sqlPassword'`n")
+      [System.IO.File]::Create($sqlPath).Dispose()
+      try {
+        $identity = [System.Security.Principal.WindowsIdentity]::GetCurrent().Name
+        icacls $sqlPath /inheritance:r /grant:r "${identity}:(F)" "SYSTEM:(R)" | Out-Null
+        if ($LASTEXITCODE -ne 0) { throw "Failed to secure temporary SQL file" }
+        [System.IO.File]::WriteAllBytes($sqlPath, $sqlBytes)
+        sqlcmd -S "(localdb)\MSSQLLocalDB" -i $sqlPath -b -x -f 65001
+        if ($LASTEXITCODE -ne 0) { throw "Failed to create the testuser login" }
+      } finally {
+        Remove-Item $sqlPath -Force -ErrorAction Stop
+      }
       sqlcmd -S "(localdb)\MSSQLLocalDB" -d StressTestDB -Q "CREATE USER testuser FOR LOGIN testuser"
       sqlcmd -S "(localdb)\MSSQLLocalDB" -d StressTestDB -Q "ALTER ROLE db_owner ADD MEMBER testuser"
       Write-Host "Database setup completed"
@@ -117,7 +130,7 @@ jobs:
 
   # Run multi-threaded stress tests in an isolated subprocess.
   - powershell: |
-      $env:DB_CONNECTION_STRING = 'Server=(localdb)\MSSQLLocalDB;Database=StressTestDB;Uid=testuser;Pwd=$(DB_PASSWORD);TrustServerCertificate=yes'
+      $env:DB_CONNECTION_STRING = "Server=(localdb)\MSSQLLocalDB;Database=StressTestDB;Uid=testuser;Pwd=$env:DB_PASSWORD;TrustServerCertificate=yes"
       Write-Host "Starting stress tests..."
 
       $xmlFile = "stress-test-results.xml"
@@ -158,17 +171,21 @@ jobs:
       Write-Host "Test failures detected or XML not found"
       exit 1
     displayName: 'Run Multi-Threaded Stress Tests'
+    env:
+      DB_PASSWORD: $(DB_PASSWORD)
     continueOnError: true
 
 
   # Run original stress tests
   - powershell: |
-      $env:DB_CONNECTION_STRING = 'Server=(localdb)\MSSQLLocalDB;Database=StressTestDB;Uid=testuser;Pwd=$(DB_PASSWORD);TrustServerCertificate=yes'
+      $env:DB_CONNECTION_STRING = "Server=(localdb)\MSSQLLocalDB;Database=StressTestDB;Uid=testuser;Pwd=$env:DB_PASSWORD;TrustServerCertificate=yes"
       python -m pytest tests/test_011_singlethreaded_stress.py -v -m "stress" --junitxml=perf-stress-test-results.xml --timeout=1800 --capture=tee-sys
       $exitCode = $LASTEXITCODE
       Write-Host "Pytest exit code: $exitCode"
       exit $exitCode
     displayName: 'Run Single-Threaded Stress Tests'
+    env:
+      DB_PASSWORD: $(DB_PASSWORD)
     continueOnError: true
 
   # Publish test results
@@ -265,20 +282,20 @@ jobs:
 
   # Start SQL Server container for stress tests
   - script: |
-      set -euxo pipefail
+      set -euo pipefail
       
       echo "Starting SQL Server 2022 container for stress tests..."
       docker run -d --name sqlserver-stress \
         --platform linux/amd64 \
         -e ACCEPT_EULA=Y \
-        -e MSSQL_SA_PASSWORD="$(DB_PASSWORD)" \
+        -e MSSQL_SA_PASSWORD \
         -p 1433:1433 \
         mcr.microsoft.com/mssql/server:2022-latest
       
       echo "Waiting for SQL Server to be ready..."
       for i in {1..30}; do
-        if docker exec sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
-          -S localhost -U SA -P "$(DB_PASSWORD)" -C -Q "SELECT 1" >/dev/null 2>&1; then
+        if docker exec -e SQLCMDPASSWORD sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
+          -S localhost -U SA -C -Q "SELECT 1" >/dev/null 2>&1; then
           echo "SQL Server is ready!"
           break
         fi
@@ -287,19 +304,22 @@ jobs:
       done
       
       echo "Creating database and user for stress tests..."
-      docker exec sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
-        -S localhost -U SA -P "$(DB_PASSWORD)" -C -Q "CREATE DATABASE StressTestDB"
-      docker exec sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
-        -S localhost -U SA -P "$(DB_PASSWORD)" -C -Q "CREATE LOGIN testuser WITH PASSWORD = '$(DB_PASSWORD)'"
-      docker exec sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
-        -S localhost -U SA -P "$(DB_PASSWORD)" -C -d StressTestDB -Q "CREATE USER testuser FOR LOGIN testuser"
-      docker exec sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
-        -S localhost -U SA -P "$(DB_PASSWORD)" -C -d StressTestDB -Q "ALTER ROLE db_owner ADD MEMBER testuser"
+      docker exec -e SQLCMDPASSWORD sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
+        -S localhost -U SA -C -Q "CREATE DATABASE StressTestDB"
+      SQL_PASSWORD=${DB_PASSWORD//\'/\'\'}
+      printf "CREATE LOGIN testuser WITH PASSWORD = '%s'\n" "$SQL_PASSWORD" | \
+        docker exec -i -e SQLCMDPASSWORD sqlserver-stress /opt/mssql-tools18/bin/sqlcmd -S localhost -U SA -C -b -x
+      docker exec -e SQLCMDPASSWORD sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
+        -S localhost -U SA -C -d StressTestDB -Q "CREATE USER testuser FOR LOGIN testuser"
+      docker exec -e SQLCMDPASSWORD sqlserver-stress /opt/mssql-tools18/bin/sqlcmd \
+        -S localhost -U SA -C -d StressTestDB -Q "ALTER ROLE db_owner ADD MEMBER testuser"
       
       echo "Database setup completed"
     displayName: 'Start SQL Server container and setup database'
     env:
       DB_PASSWORD: $(DB_PASSWORD)
+      MSSQL_SA_PASSWORD: $(DB_PASSWORD)
+      SQLCMDPASSWORD: $(DB_PASSWORD)
 
   # Run multi-threaded stress tests in an isolated subprocess.
   - script: |