# CVE-2026-34528: File Browser's Signup Grants Execution Permissions When Default Permissions Includes Execution > Unauthenticated users can gain shell execution rights if signup and server-side execution are enabled with specific default permissions. - **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 1 Apr 2026 - **Updated:** 2 Apr 2026 - **Also known as:** GHSA-x8jc-jvqm-pm3f, GO-2026-5747 ## What is CVE-2026-34528? CVE-2026-34528 is a high-severity vulnerability in filebrowser, published on 1 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior to version 2.62.2, the signupHandler in File Browser applies default user permissions via d.settings.Defaults.Apply(user), then strips only Admin. The Execute permission and Commands list from the default user template are not stripped. When an administrator has enabled signup, server-side execution, and set Execute=true in the default user template, any unauthenticated user who self-registers inherits shell execution capabilities and can run arbitrary commands on the server. This issue has been patched in version 2.62.2. Weakness: CWE-269 (Improper Privilege Management) ## Which versions are affected by CVE-2026-34528? 4 open source packages ship an affected version, including github.com/filebrowser/filebrowser/v2 and github.com/filebrowser/filebrowser. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.62.2 | | `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.62.2 | | `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.62.2 | | `github.com/filebrowser/filebrowser` | Go | All versions | None | Products: Filebrowser Filebrowser. ## How do I fix CVE-2026-34528? Upgrade github.com/filebrowser/filebrowser/v2 to 2.62.2 or later. ## Is CVE-2026-34528 being exploited? It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34528 exists. ## Other vulnerabilities in filebrowser - [CVE-2026-32760](https://insights.sbomify.com/CVE-2026-32760/): File Browser Self Registration Grants Any User Admin Access When Default Permissions Include Admin (critical 10.0) - [CVE-2026-29188](https://insights.sbomify.com/CVE-2026-29188/): File Browser: TUS Delete Endpoint Bypasses Delete Permission Check (critical 9.1) - [CVE-2023-39612](https://insights.sbomify.com/CVE-2023-39612/): Cross-site scripting in n/a (critical 9.0) - [CVE-2026-30934](https://insights.sbomify.com/CVE-2026-30934/): FileBrowser Quantum: Stored XSS in public share page via unsanitized share metadata (text/template misuse) (high 8.9) - [CVE-2021-46398](https://insights.sbomify.com/CVE-2021-46398/): Cross-Site Request Forgery in Filebrowser (high 8.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-34528 and fix it if it is affected. What it is: CVE-2026-34528 is a high-severity vulnerability in filebrowser, published on 1 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34528 exists. Affected packages and fixed versions: - github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.62.2 - github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.62.2 - github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.62.2 - github.com/filebrowser/filebrowser (Go): affected all versions; no fix listed Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-34528/ (Markdown: https://insights.sbomify.com/CVE-2026-34528/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-34528 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-34528 - OSV: https://osv.dev/vulnerability/CVE-2026-34528 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-34528/ Summaries are generated and may contain mistakes; the official description above is the record.