CVE-2026-53758 json
Emlog: Stored XSS via Parsedown Markdown Processing - Raw HTML Not Sanitized
published 2026-09-04 2 mo ago modified 2026-09-09 1 mo ago also EUVD-2026-71624
- cvss
- 8.7
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 38%
- public exploits
- 0
- none known
Summary
Emlog is an open source website building system. In versions 2.6.29 and prior, article content is processed by Parsedown without enabling safe mode, which means raw HTML including <script> tags embedded in Markdown is passed through unescaped. The output is rendered with no additional sanitization, resulting in stored XSS visible to all site visitors. At time of publication, there are no publicly known patches.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 1 mo ago
Exploit prediction
0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/emlog/emlog/security/advisories/GHSA-35vc-2gv4-mw77 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/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 |
Affected products
- emlog emlog
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
Sources
- CVE List CVE-2026-53758
- NVD CVE-2026-53758
Fencer Vulns 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.