Auth bypass in Sdcb Chats
CVE-2026-82906
A flaw has been found in sdcb chats up to 1.12.0. This impacts the function DownloadPublic of the file src/BE/web/Controllers/Chats/Files/FileController.cs of the component Signed File Download Endpoint. This manipulation causes missing authentication. Remote exploitation of the attack is possible. The attack's complexity is rated as high. The exploitability is said to be difficult. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.006 (46.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 46.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.002
Affected products
- Sdcb Chats — versions 1.0, 1.1, 1.10
Weakness classification (CWE)
References
- vuldb.com/vuln/397286 (technical-description, vdb-entry)
- vuldb.com/vuln/397286/cti (signature, permissions-required)
- vuldb.com/cve/CVE-2026-82906 (third-party-advisory)
- vuldb.com/submit/877767 (third-party-advisory)
- github.com/yaowenxiao721/Poc/blob/main/sdcb-chats/chats-poc-2.md (exploit)
Frequently asked questions
- What is CVE-2026-82906?
- CVE-2026-82906 is a low-severity vulnerability in Sdcb Chats, classified under Improper Authentication. CVSS score: 3.7/10. Published 2026-08-31.
- How severe is CVE-2026-82906?
- Low severity. CVSS v3 base score is 3.7 out of 10.