Is CVE-2026-110103 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-110103 being exploited in the wild.

How severe is CVE-2026-110103?

Medium severity, with a CVSS score of 5.4, published 13 October 2026.

Is there a fix for CVE-2026-110103?

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-2026-110103 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-110103?

Check whether you run Mlogclub Bbs-Go 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-2026-110103: bbs-go stored cross-site scripting in file upload

CVE-2026-110103 · Severity: medium · CVSS 5.4 · Published 2026-10-13

bbs-go is a forum or community platform software. The vulnerability allows authenticated users to upload HTML or SVG files by bypassing file type validation, which are then served directly from the forum's web server. When administrators or other users visit URLs to these malicious files, arbitrary JavaScript executes in their browser with the forum's privileges, potentially exposing sensitive data or allowing account compromise.

Technologies: Mlogclub Bbs-Go. Vendors: Mlogclub.

Quick answers

Is CVE-2026-110103 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-110103 being exploited in the wild.
How severe is CVE-2026-110103?: Medium severity, with a CVSS score of 5.4, published 13 October 2026.
Which products and versions are affected?: Mlogclub Bbs-Go through 4.4.6.
Is there a fix for CVE-2026-110103?: 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-2026-110103 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-110103?: Check whether you run Mlogclub Bbs-Go 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

The upload handler in POST /api/upload extracts the Content-Type header from the multipart request but does not validate the actual file contents, allowing an attacker to spoof the Content-Type (e.g., claiming an HTML file is an image) and bypass file-type restrictions. Files are stored at /res and served inline rather than as attachments, causing browsers to execute script within the forum's origin. An authenticated attacker can craft a URL to the uploaded file and send it to administrators to trigger code execution.

Affected products

mlogclub bbs-go through 4.4.6

Timeline

2026-10-13: disclosed

References

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