Selenium Chromedriver server times out despite being available

I have a Java Selenium project that will not run on my machine, but does run on coworkers' machines with the same OS version (OSX 10.13.1), Chrome browser version (63.0.3239.84), and chromedriver version (2.34). I get the message:

Starting ChromeDriver 2.34.522932 (4140ab217e1ca1bec0c4b4d1b148f3361eb3a03e) on port 18633
Only local connections are allowed.

org.openqa.selenium.WebDriverException: Timed out waiting for driver server to start.
Build info: version: '3.8.1', revision: '6e95a6684b', time: '2017-12-01T18:33:54.468Z'
System info: host: 'localhost', ip: 'fe80:0:0:0:1cc9:e0ab:f4e5:dd34%en0', os.name: 'Mac OS X', os.arch: 'x86_64', os.version: '10.13.1', java.version: '1.8.0_20'
Driver info: driver.version: ChromeDriver
...
Caused by: org.openqa.selenium.net.UrlChecker$TimeoutException: Timed out waiting for [http://localhost:18633/status] to be available after 20005 ms
    at org.openqa.selenium.net.UrlChecker.waitUntilAvailable(UrlChecker.java:100)
    at org.openqa.selenium.remote.service.DriverService.waitUntilAvailable(DriverService.java:187)
    ... 28 more
Caused by: java.util.concurrent.TimeoutException
    at java.util.concurrent.FutureTask.get(FutureTask.java:205)
    at com.google.common.util.concurrent.SimpleTimeLimiter.callWithTimeout(SimpleTimeLimiter.java:149)
    at org.openqa.selenium.net.UrlChecker.waitUntilAvailable(UrlChecker.java:75)
    ... 29 more

however when I open http://localhost:18633/status in my browser I get a valid response:

{"sessionId":"","status":0,"value":{"build":{"version":"alpha"},"os":{"arch":"x86_64","name":"Mac OS X","version":"10.13.1"}}}

I've tried swapping out chromedriver binaries, but I'm not really sure what else to do. I get similar issues with geckodriver, but that may or may not be the same issue. I have also tried creating a new user on my system and running it from that account, to account for user settings - No luck.

What am I missing here? What info would be helpful to debug this problem?