What is CVE-2023-50883?

CVE-2023-50883 is a medium-severity vulnerability in Onlyoffice Document Server, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2024-09-09.

How severe is CVE-2023-50883?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Onlyoffice Document Server

CVE-2023-50883

ONLYOFFICE Docs before 8.0.1 allows XSS because a macro is an immediately-invoked function expression (IIFE), and therefore a sandbox escape is possible by directly calling the constructor of the Function object. NOTE: this issue exists because of an incorrect fix for CVE-2021-43446.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2024-09-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (47.0th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Onlyoffice Document Server

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.onlyoffice.com/ (Product)
www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2023-027.txt (Exploit, Third Party Advisory)
www.syss.de/pentest-blog/cross-site-scripting-schwachstelle-in-onlyoffice-docs-… (Third Party Advisory)

Frequently asked questions

What is CVE-2023-50883?: CVE-2023-50883 is a medium-severity vulnerability in Onlyoffice Document Server, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2024-09-09.
How severe is CVE-2023-50883?: Medium severity. CVSS v3 base score is 6.1 out of 10.