A researcher has earned $20,000 from GitLab after reporting a critical vulnerability that could have been exploited to obtain sensitive information from a server and to execute arbitrary code.
The vulnerability was discovered in March by William Bowling, who noticed that an attacker could obtain arbitrary files from a server when moving an issue from one GitLab project to another. The flaw was caused by the lack of validation for file names in the UploadsRewriter function.
He demonstrated how an attacker could exploit the vulnerability to read arbitrary files from the server, including ones storing configurations, tokens, and other private data.
After he reported his findings to GitLab through the company’s bug bounty program on HackerOne, Bowling continued to analyze the issue and discovered that it could also lead to remote code execution.
The flaw was found to impact both local GitLab installations and gitlab.com. As GitLab developers pointed out, an attacker could have exploited the vulnerability by creating their own project or group and moving an issue from one project to another.
The vulnerability was patched within days by GitLab, which decided to pay out a $20,000 bounty for the researcher’s findings. The report describing the security hole was made public this week.
In recent months, Bowling earned a total of more than $50,000 from GitLab for several critical and high-severity vulnerabilities. GitLab reported in December 2019 that it had paid out over half a million dollars through its bug bounty program over the past year.