XSS in Fedify-Dev Hollo

CVE-2025-53941

Hollo is a federated single-user microblogging software designed to be federated through ActivityPub. Versions prior to 0.6.5 allow HTML form elements to be submitted, making the software vulnerable to HTML injection. Version 0.6.5 fixes the issue.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

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: 0.002 (13.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 13th percentile — 13.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-53941: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-53941?
CVE-2025-53941 is a medium-severity vulnerability in Fedify-Dev Hollo, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2025-07-17.
How severe is CVE-2025-53941?
Medium severity. CVSS v3 base score is 6.1 out of 10.