I don't think so. Anyone with the Browse Project permission can view an issue's time tracking information (https://confluence.atlassian.com/display/JIRA/Logging+Work+on+an+Issue).
You can control, who can log work on an issue via the project permissions (https://confluence.atlassian.com/display/JIRA/Managing+Project+Permissions) , but everyone who is able to look at the issue can see the already logged work too.
Or with a bit of velocity code in the description part of one of the custom fields. See this post in earlier forums for a similar case
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