Collabora Online is a collaborative online office suite based on LibreOffice technology. In the mobile (Android/iOS) device variants of Collabora Online it was possible to inject JavaScript via url encoded values in links contained in documents. Since the Android JavaScript interface allows access to internal functions, the likelihood that the app could be compromised via this vulnerability is considered high. Non-mobile variants are not affected. Mobile variants should update to the latest version provided by the platform appstore. There are no known workarounds for this vulnerability.
Weakness
The web application improperly neutralizes user-controlled input for executable script disguised with URI encodings.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Online |
Collabora |
* |
24.04.6.2 (excluding) |
Potential Mitigations
- Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8. When an encoding is not specified, a downstream component may choose a different encoding, either by assuming a default encoding or automatically inferring which encoding is being used, which can be erroneous. When the encodings are inconsistent, the downstream component might treat some character or byte sequences as special, even if they are not special in the original encoding. Attackers might then be able to exploit this discrepancy and conduct injection attacks; they even might be able to bypass protection mechanisms that assume the original encoding is also being used by the downstream component.
- The problem of inconsistent output encodings often arises in web pages. If an encoding is not specified in an HTTP header, web browsers often guess about which encoding is being used. This can open up the browser to subtle XSS attacks.
References