RCE in Showdoc
CVE-2026-120203
ShowDoc 2.8.14 before 3.9.6 contains a code injection vulnerability in its Mock feature that allows authenticated users to execute shell commands through mockjs templates. Attackers can store a template via MockController::add with escaped parentheses that mockjs evaluates with eval(), then trigger it through MockController::infoByKey to run commands, as root in the official Docker image.
Vulnerability class: RCE (Remote Code Execution)
Published .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
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/star7th/showdoc/commit/5a2087a3f408f5266f61e9e2fb98845ef4788288 (patch)
- gist.github.com/LioTree/028af150fd991cf9924dd2c7d5912e54 (technical-description)
- github.com/star7th/showdoc/blob/v3.9.5/mock/index.js (technical-description)
- github.com/star7th/showdoc (product)
- www.vulncheck.com/advisories/showdoc-2.8.14-before-3.9.6-code-injection-via-moc… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-120203?
- CVE-2026-120203 is a high-severity vulnerability in Showdoc, classified under Code Injection. CVSS score: 8.8/10. Published 2026-10-31.
- How severe is CVE-2026-120203?
- High severity. CVSS v3 base score is 8.8 out of 10.