CVE-2025-64711
LOWCVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
Lifecycle Timeline
4Description
PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Starting in version 1.7.7 and prior to version 2.0.3, dragging a file whose filename contains HTML is reflected verbatim into the page via the drag-and-drop helper, so any user who drops a crafted file on PrivateBin will execute arbitrary JavaScript within their own session (self-XSS). This allows an attacker who can entice a victim to drag or otherwise attach such a file to exfiltrate plaintext, encryption keys, or stored pastes before they are encrypted or sent. Certain conditions must exist for the vulnerability to be exploitable. Only macOS or Linux users are affected, due to the way the `>` character is treated in a file name on Windows. The PrivateBin instance needs to have file upload enabled. An attacker needs to have access to the local file system or somehow convince the user to create (or download) a malicious file (name). An attacker needs to convince the user to attach that malicious file to PrivateBin. Any Mac / Linux user who can be tricked into dragging a maliciously named file into the editor is impacted; code runs in the origin of the PrivateBin instance they are using. Attackers can steal plaintext, passphrases, or manipulate the UI before data is encrypted, defeating the zero-knowledge guarantees for that victim session, assuming counter-measures like Content-Security-Policy (CSP) have been disabled. If CSP is not disabled, HTML injection attacks may be possible - like redirecting to a foreign website, phishing etc. As the whole exploit needs to be included in the file name of the attached file and only affects the local session of the user (aka it is neither persistent nor remotely executable) and that user needs to interact and actively attach that file to the paste, the impact is considered to be practically low. Version 2.0.3 patches the issue.
Analysis
PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Rated low severity (CVSS 3.9), this vulnerability is low attack complexity. Public exploit code available.
Technical Context
This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Starting in version 1.7.7 and prior to version 2.0.3, dragging a file whose filename contains HTML is reflected verbatim into the page via the drag-and-drop helper, so any user who drops a crafted file on PrivateBin will execute arbitrary JavaScript within their own session (self-XSS). This allows an attacker who can entice a victim to drag or otherwise attach such a file to exfiltrate plaintext, encryption keys, or stored pastes before they are encrypted or sent. Certain conditions must exist for the vulnerability to be exploitable. Only macOS or Linux users are affected, due to the way the `>` character is treated in a file name on Windows. The PrivateBin instance needs to have file upload enabled. An attacker needs to have access to the local file system or somehow convince the user to create (or download) a malicious file (name). An attacker needs to convince the user to attach that malicious file to PrivateBin. Any Mac / Linux user who can be tricked into dragging a maliciously named file into the editor is impacted; code runs in the origin of the PrivateBin instance they are using. Attackers can steal plaintext, passphrases, or manipulate the UI before data is encrypted, defeating the zero-knowledge guarantees for that victim session, assuming counter-measures like Content-Security-Policy (CSP) have been disabled. If CSP is not disabled, HTML injection attacks may be possible - like redirecting to a foreign website, phishing etc. As the whole exploit needs to be included in the file name of the attached file and only affects the local session of the user (aka it is neither persistent nor remotely executable) and that user needs to interact and actively attach that file to the paste, the impact is considered to be practically low. Version 2.0.3 patches the issue. Affected products include: Privatebin. Version information: version 1.7.7.
Affected Products
Privatebin.
Remediation
A vendor patch is available. Apply the latest security update as soon as possible. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.
Priority Score
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External POC / Exploit Code
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