XSS in Privatebin

CVE-2025-62796

PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Versions 1.7.7 through 2.0.1 allow persistent HTML injection via the unsanitized attachment filename (attachment_name) when attachments are enabled. An attacker can modify attachment_name before encryption so that, after decryption, arbitrary HTML is inserted unescaped into the page near the file size hint, enabling redirect (e.g., meta refresh) and site defacement and related phishing attacks. Script execution is normally blocked by the recommended Content Security Policy, limiting confidentiality impact. The issue was introduced in 1.7.7 and fixed in 2.0.2. Update to 2.0.2 or later. Workarounds include enforcing the recommended CSP, deploying PrivateBin on a separate domain, or disabling attachments.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (19.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-62796?
CVE-2025-62796 is a medium-severity vulnerability in Privatebin, classified under Cross-site Scripting. CVSS score: 5.8/10. Published 2025-10-28.
How severe is CVE-2025-62796?
Medium severity. CVSS v3 base score is 5.8 out of 10.