CVE-2021-47839 (GCVE-0-2021-47839)
Vulnerability from cvelistv5 – Published: 2026-01-16 19:09 – Updated: 2026-07-15 01:28
VLAI
EPSS
VEX
Title
Marky 0.0.1 - Persistent Cross-Site Scripting
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-16 21:00 UTC
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
VulnCheck
CNA
References
7 references
| URL | Tags |
|---|---|
| https://www.exploit-db.com/exploits/49831 | exploit |
| https://github.com/vesparny/marky | product |
| https://imgur.com/a/qclfrUx | exploit |
| https://www.vulncheck.com/advisories/marky-persis… | third-party-advisory |
| https://access.redhat.com/security/cve/CVE-2021-47839 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2430451 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
Impacted products
3 products
| Vendor | Product | Version | |
|---|---|---|---|
| vesparny | Marky |
Affected:
0.0.1
cpe:2.3:a:marky_project:marky:0.0.1:*:*:*:*:*:*:* |
|
| Red Hat | Logging Subsystem for Red Hat OpenShift |
cpe:/a:redhat:logging:5
|
|
| Red Hat | Red Hat Satellite 6 |
cpe:/a:redhat:satellite:6
|
Date Public
2021-04-05 00:00
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