Is CVE-2026-102248 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-102248 being exploited in the wild.

How severe is CVE-2026-102248?

High severity, with a CVSS score of 7.3, published 29 September 2026.

Which products and versions are affected?

Rebuild up to 4.4.7 and 4.5.0-beta5.

Is there a fix for CVE-2026-102248?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-102248 attacked?

It is attacked over the network.

Am I affected by CVE-2026-102248?

Check whether you run Rebuild 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-2026-102248: Rebuild authentication bypass in login endpoint

CVE-2026-102248 · Severity: high · CVSS 7.3 · Published 2026-09-29

Rebuild is an open-source application with a login system that can be bypassed without credentials. An attacker who can access any public shared link can extract a security token from it and use that token to log in as an administrator with full system access. This allows complete compromise of the application, including reading sensitive data, modifying users and system configuration, and establishing persistent admin sessions.

Quick answers

Is CVE-2026-102248 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-102248 being exploited in the wild.
How severe is CVE-2026-102248?: High severity, with a CVSS score of 7.3, published 29 September 2026.
Which products and versions are affected?: Rebuild up to 4.4.7 and 4.5.0-beta5.
Is there a fix for CVE-2026-102248?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-102248 attacked?: It is attacked over the network.
Am I affected by CVE-2026-102248?: Check whether you run Rebuild 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

An improper authentication vulnerability (CWE-287) exists in the /user/login endpoint where CSRF tokens from public sharing contexts (/s/{shareKey}) are accepted as login credentials without validating token purpose or binding. An unauthenticated attacker can extract the rb.csrfToken value from any public share page and submit it via the token parameter to /user/login to establish a SYSTEM_USER administrator session. The vulnerability requires only network access and knowledge of a valid public share URL, with no authentication or user interaction needed.

Affected products

Rebuild up to 4.4.7 and 4.5.0-beta5

Timeline

2026-08-17: disclosed
2026-09-29: advisory

References

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