Buffer overflow in Ritlabs Tinyweb Server
CVE-2026-12200
A security vulnerability has been detected in Ritlabs TinyWeb Server up to 1.94 on Win32. This impacts an unknown function in the library libeay32.dll.html of the component Header Handler. The manipulation of the argument Authorization leads to stack-based buffer overflow. The attack can be initiated remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.003 (25.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 25.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Ritlabs Tinyweb Server — versions 1.0, 1.1, 1.2
Weakness classification (CWE)
References
- nathan2.com/posts/tinyweb/ (exploit)
- vuldb.com/cve/CVE-2026-12200 (third-party-advisory)
- vuldb.com/submit/829894 (third-party-advisory)
- vuldb.com/vuln/370842 (technical-description, vdb-entry)
- vuldb.com/vuln/370842/cti (signature, permissions-required)
Frequently asked questions
- What is CVE-2026-12200?
- CVE-2026-12200 is a high-severity vulnerability in Ritlabs Tinyweb Server, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.3/10. Published 2026-06-15.
- How severe is CVE-2026-12200?
- High severity. CVSS v3 base score is 7.3 out of 10.