Is CVE-2026-54685 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-54685 being exploited in the wild.

How severe is CVE-2026-54685?

Medium severity, with a CVSS score of 5.3, published 20 July 2026.

Which products and versions are affected?

github.com/gtsteffaniak/filebrowser/backend (Go) < 0.0.0-20260317230626-af08800667b8, SEMVER:introduced=0,fixed=0.0.0-20260317230626-af08800667b8; Gtsteffaniak FileBrowser Quantum < 0.0.0-20260317230626-af08800667b8, < 1.3.2-beta.

Is there a fix for CVE-2026-54685?

Yes. github.com/gtsteffaniak/filebrowser/backend (Go): upgrade to 0.0.0-20260317230626-af08800667b8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-54685 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-54685?

Check whether you run github.com/gtsteffaniak/filebrowser/backend (Go) or Gtsteffaniak FileBrowser Quantum at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-54685: gtsteffaniak FileBrowser Quantum username enumeration via timing side-channel

Q: Is there a fix for CVE-2026-54685?

Yes. github.com/gtsteffaniak/filebrowser/backend (Go): upgrade to 0.0.0-20260317230626-af08800667b8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-54685 attacked?

It is attacked over the network, in a network appliance.

Q: Am I affected by CVE-2026-54685?

Check whether you run github.com/gtsteffaniak/filebrowser/backend (Go) or Gtsteffaniak FileBrowser Quantum at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-54685 · Severity: medium · CVSS 5.3 · Published 2026-07-20

FileBrowser Quantum is a self-hosted web application used for managing files remotely. A security flaw in its login system allows unauthorized individuals to determine which usernames exist on the server by measuring how long the system takes to respond to login attempts. This information can be used to launch more targeted attacks, such as password guessing or social engineering, against known valid accounts.

Technologies: github.com/gtsteffaniak/filebrowser/backend (Go), Gtsteffaniak FileBrowser Quantum. Vendors: Go, Gtsteffaniak.

Quick answers

Is CVE-2026-54685 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-54685 being exploited in the wild.
How severe is CVE-2026-54685?: Medium severity, with a CVSS score of 5.3, published 20 July 2026.
Which products and versions are affected?: github.com/gtsteffaniak/filebrowser/backend (Go) < 0.0.0-20260317230626-af08800667b8, SEMVER:introduced=0,fixed=0.0.0-20260317230626-af08800667b8; Gtsteffaniak FileBrowser Quantum < 0.0.0-20260317230626-af08800667b8, < 1.3.2-beta.
Is there a fix for CVE-2026-54685?: Yes. github.com/gtsteffaniak/filebrowser/backend (Go): upgrade to 0.0.0-20260317230626-af08800667b8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-54685 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-54685?: Check whether you run github.com/gtsteffaniak/filebrowser/backend (Go) or Gtsteffaniak FileBrowser Quantum at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/gtsteffaniak/filebrowser/backend (Go): upgrade to 0.0.0-20260317230626-af08800667b8 or later
```
go get github.com/gtsteffaniak/filebrowser/backend@v0.0.0-20260317230626-af08800667b8
```

Technical details

The `/api/auth/login` authentication endpoint in FileBrowser Quantum prior to version 1.3.2-beta does not execute in constant time, leading to a CWE-208 observable timing discrepancy. The root cause is located in the `Auth` function of `JSONAuth` within `auth/json.go`, which returns an error immediately if a username is not found in the database but proceeds to a computationally expensive bcrypt password comparison if the username is valid. An unauthenticated remote attacker can measure these millisecond-level differences (e.g., ~1-4ms for invalid users vs. ~40-50ms for valid users) to enumerate valid accounts. The vulnerability is remediated in version 1.3.2-beta by ensuring the authentication logic maintains consistent execution time regardless of username validity.

Affected products

gtsteffaniak FileBrowser Quantum < 1.3.2-beta

Identifiers

CVE-2026-54685
GHSA-7789-65hx-f26w
GO-2026-4820

Timeline

2026-03-21: patched: Version 1.3.2-beta released with fix
2026-07-20: disclosed: Public advisory and CVE published

References

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