Is CVE-2026-61503 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-61503 being exploited in the wild.

How severe is CVE-2026-61503?

Medium severity, with a CVSS score of 5.3, published 13 July 2026.

Which products and versions are affected?

Rejetto HFS 3.0.0 through 3.2.0.

Is there a fix for CVE-2026-61503?

A patch was published on 2026-07-13: Version 3.2.1 released to address the vulnerability. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-61503 attacked?

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

Am I affected by CVE-2026-61503?

Check whether you run Rejetto HFS 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-2026-61503: Rejetto HFS username enumeration in login endpoint

CVE-2026-61503 · Severity: medium · CVSS 5.3 · Published 2026-07-13

Rejetto HFS, a popular file-sharing server, contains a flaw that allows unauthorized individuals to identify valid usernames on the system. By observing differences in how the login page responds to various inputs, an attacker can confirm which accounts exist, including administrative ones. This information significantly simplifies subsequent attacks, such as password guessing or attempts to hijack user sessions.

Technologies: Rejetto HFS. Vendors: Rejetto.

Quick answers

Is CVE-2026-61503 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-61503 being exploited in the wild.
How severe is CVE-2026-61503?: Medium severity, with a CVSS score of 5.3, published 13 July 2026.
Which products and versions are affected?: Rejetto HFS 3.0.0 through 3.2.0.
Is there a fix for CVE-2026-61503?: A patch was published on 2026-07-13: Version 3.2.1 released to address the vulnerability. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-61503 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-61503?: Check whether you run Rejetto HFS 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.

Technical details

A username enumeration vulnerability exists in Rejetto HFS versions 3.0.0 through 3.2.0 due to an observable response discrepancy (CWE-204) at the login endpoint. A remote, unauthenticated attacker can distinguish between valid and invalid usernames based on the server's response behavior. This allows for the discovery of valid account names, including the default 'admin' account, which can be leveraged for targeted brute-force or session-forgery attacks. The issue is resolved in version 3.2.1.

Affected products

Rejetto HFS (HTTP File Server) 3.0.0 through 3.2.0

Timeline

2026-07-13: advisory: NVD and VulnCheck published the advisory.
2026-07-13: patched: Version 3.2.1 released to address the vulnerability.

References

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