Stored Cross-Site Scripting in FileCodeBox by Vastsa
CVE-2026-129170

5.3MEDIUM

Key Information:

Vendor

Vastsa

Status
Filecodebox
Vendor
CVE Published:
13 November 2026

What is CVE-2026-129170?

FileCodeBox versions 2.2.1 to 2.8.4 exhibit a stored cross-site scripting vulnerability in the renderMarkdownPreview function. This vulnerability allows unauthenticated attackers to input malicious text, leveraging a series of nested blockquote markers followed by HTML payloads. When the marked parser encounters an error, it returns this unsanitized text, enabling the execution of scripts that can extract sensitive information like admin tokens from localStorage, posing a significant risk to user security.

Affected Version(s)

FileCodeBox 2.2.1 <= 2.8.4

References

https://vul.yulun.ac.cn/20261027/filecodebox/
third-party-advisory
https://github.com/vastsa/FileCodeBox/issues/557
issue-tracking
https://github.com/vastsa/FileCodeBoxFronted/commit/4c404...
patch

CVSS V4

Score:
5.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Wu Yulun
.