RCE in Shd101wyy Crossnote
CVE-2026-11422
Markdown Preview Enhanced 0.8.x with crossnote engine 0.9.28 contains a code injection vulnerability in the WaveDrom rendering pipeline that allows attackers to execute arbitrary JavaScript by embedding malicious content in a wavedrom fenced code block within a crafted Markdown document. Attackers can exploit the unsanitized passing of wavedrom block content to window.eval() in the VS Code webview context to abuse the extension's message passing and invoke arbitrary file writes on the local filesystem.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (4.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 5th percentile — 4.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Shd101wyy Crossnote — versions 0
- Shd101wyy Markdown Preview Enhanced — versions 0
Weakness classification (CWE)
References
- github.com/shd101wyy/crossnote/commit/5588ca2121c3da43fe331575dc5cf4ef347b91ee (patch)
- github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/dcd80281c986293b93… (patch)
- github.com/shd101wyy/vscode-markdown-preview-enhanced/issues/2315 (issue-tracking, technical-description)
- www.vulncheck.com/advisories/markdown-preview-enhanced-x-code-injection-via-wav… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-11422?
- CVE-2026-11422 is a high-severity vulnerability in Shd101wyy Crossnote, classified under Eval Injection. CVSS score: 7.1/10. Published 2026-06-05.
- How severe is CVE-2026-11422?
- High severity. CVSS v3 base score is 7.1 out of 10.