CVE-2026-129170 json
FileCodeBox 2.2.1 through 2.8.4 Stored XSS via Markdown Preview Parser Error
published yesterday modified yesterday also EUVD-2026-125597
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 19%
- public exploits
- 0
- none known
Summary
FileCodeBox 2.2.1 through 2.8.4 contains a stored cross-site scripting vulnerability in renderMarkdownPreview, which returns unsanitized text when the marked parser throws. Unauthenticated attackers can share text with thousands of nested blockquote markers followed by HTML payloads, executing script that steals the admin token from localStorage.
Patch / fix
Is CVE-2026-129170 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-14).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N |
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected products
- vastsa FileCodeBox
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/vastsa/FileCodeBoxFronted/commit/4c40406d366af1583a3ba2327366b7a62d765537
patch
-
vul.yulun.ac.cn
/20261027/filecodebox/
third-party-advisory
-
github.com
/vastsa/FileCodeBox/issues/557
issue-tracking
-
github.com
/vastsa/FileCodeBoxFronted/blob/bcc1dbda06b772d6f4afbcc12c6f12e60bbbc7da/src/utils/content-preview.ts#L43-L57
technical-description
-
github.com
/vastsa/FileCodeBoxFronted/blob/bcc1dbda06b772d6f4afbcc12c6f12e60bbbc7da/src/components/common/ContentPreviewM
technical-description
-
vulncheck.com
/advisories/filecodebox-2.2.1-through-2.8.4-stored-xss-via-markdown-preview-parser-error
third-party-advisory
Sources
- CVE List CVE-2026-129170
- NVD CVE-2026-129170
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.