Confluence UI shows garbled or corrupt text on CAPTCHA, macros and/or diagrams due to missing fonts
This Knowledge Base article was written specifically for the Atlassian Server platform. Due to the Functional differences in Atlassian Cloud, the contents of this article cannot be applied to Atlassian Cloud applications.
Following a Confluence upgrade running on an older Linux distribution, you might encounter a problem where certain system text in the application will appear to be garbled and look like symbols instead of regular alphanumeric letters.
You will not see any errors in the logs relating to the issue, however, you might see warnings about fonts in general.
This has been observed in the following areas of Confluence
Inline charts and diagrams
In order to identify whether you are affected by this issue, you will need to answer the below questions:
- Did you upgrade Confluence Server recently to a new version?
- Are you running an older version of a Linux distribution that is behind current release cycle (possibly more than 3+ years old)?
If you answered yes to both of the above questions, you might be missing fonts on the OS level that more recent versions of Confluence depend on to render pages properly. Bug report for reference: - CONFSERVER-54067Getting issue details... STATUS
Uninstall lyx-fonts package (Lyx/MathML fonts - A collection of Math symbol fonts for lyx)
You will need to check and install the following font packages. You can use any package manager you like. For this example, we will be using
yum install ghostscript yum install dejavu-fonts-common yum install dejavu-sans-fonts yum install dejavu-sans-mono-fonts yum install motif
Some versions of ghostscript packages can be affected by security vulnerability CVE-2018-16509 discovered in September 2018.
for more details see
In order for Confluence to pick up the changes, please apply the below steps:
- Stop Confluence
Rebuild the font cache by using the following command:
- Clear the Confluence Plugins Cache.
- Perform a Content Index Rebuild.
- Start Confluence.
- Clear your browser cache and verify Confluence is presenting the text properly.
- If you still see garbled text, try rebooting the server, then check again.