XSS in Vesparny Marky
CVE-2021-47839
Marky 0.0.1 contains a persistent cross-site scripting vulnerability that allows attackers to inject malicious scripts into markdown files. Attackers can upload crafted markdown files with embedded JavaScript payloads that execute when the file is opened, potentially enabling remote code execution.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.005 (38.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.8% 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: 0.005 · change: +0.000
Affected products
- Vesparny Marky — versions 0.0.1
Weakness classification (CWE)
References
- www.exploit-db.com/exploits/49831 (exploit)
- github.com/vesparny/marky (product)
- imgur.com/a/qclfrUx (exploit)
- www.vulncheck.com/advisories/marky-persistent-cross-site-scripting (third-party-advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2021-47839?
- CVE-2021-47839 is a high-severity vulnerability in Vesparny Marky, classified under Cross-site Scripting. CVSS score: 7.2/10. Published 2026-01-16.
- How severe is CVE-2021-47839?
- High severity. CVSS v3 base score is 7.2 out of 10.