XSS in Mlogclub Bbs-Go
CVE-2026-110103
bbs-go through 4.4.6 contains a stored cross-site scripting vulnerability that allows authenticated users to upload HTML or SVG files by spoofing the multipart Content-Type in POST /api/upload. Attackers can upload script-bearing documents served inline from /res and send their URLs to administrators, executing script on the forum's origin.
Vulnerability class: XSS (Cross-Site Scripting)
Published .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/mlogclub/bbs-go/issues/305 (issue-tracking, technical-description)
- github.com/mlogclub/bbs-go/blob/v4.4.6/internal/pkg/uploader/uploader.go (technical-description)
- github.com/mlogclub/bbs-go/blob/v4.4.6/internal/handlers/api/upload_handlers.go (technical-description)
- github.com/mlogclub/bbs-go/pull/306 (issue-tracking, patch)
- github.com/mlogclub/bbs-go/commit/5bebf98bb9e0ac5162d4f8faf7a65fc0d496a362 (patch)
- www.vulncheck.com/advisories/bbs-go-through-4.4.6-stored-xss-via-image-upload-c… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-110103?
- CVE-2026-110103 is a medium-severity vulnerability in Mlogclub Bbs-Go, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-10-13.
- How severe is CVE-2026-110103?
- Medium severity. CVSS v3 base score is 5.4 out of 10.