Client-Side Enforcement of Server-Side Security Affecting github.com/gtsteffaniak/filebrowser/backend/http package, versions <1.2.2-stable>=1.3.0-beta <1.3.1-beta
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-GOLANG-GITHUBCOMGTSTEFFANIAKFILEBROWSERBACKENDHTTP-15444912
- published10 Mar 2026
- disclosed9 Mar 2026
- creditMichael Coxe
Introduced: 9 Mar 2026
CVE-2026-30933 Â (opens in a new tab)How to fix?
Upgrade github.com/gtsteffaniak/filebrowser/backend/http to version 1.2.2-stable, 1.3.1-beta or higher.
Overview
Affected versions of this package are vulnerable to Client-Side Enforcement of Server-Side Security via the shareInfoHandler process. An attacker can gain unauthorized access to confidential shared files by querying the public API endpoint and extracting tokenized download URLs, which allow direct file downloads without password authentication.