Category Archives: advisory

Cross domain access to object constructors can be used to facilitate cross-site scripting – Opera Security Advisories

Severity High Description JavaScripts are able to redefine and override the methods of native objects. They may also do this with the native objects of any document that shares the same origin. By redefining the methods of another document through the constructor property of the document’s host objects, a malicious script can cause Opera to…

Specially crafted SVG images can allow execution of arbitrary code – Opera Security Advisories

Severity Critical Description Opera can display images created using the Scalable Vector Graphics (SVG) format. Specially crafted and malformed SVG images may cause Opera to crash when their documents are unloaded, and the crash may allow execution of malicious arbitrary code. To inject code, additional techniques will have to be employed. Opera’s Response Opera Software…

Internet shortcuts used for phishing in elements – Opera Security Advisories

Severity None Description Websites may occasionally want to display image content from untrusted sources. A phishing attack may be carried out by the untrusted source, by displaying malicious instructions on the image, or by navigating the containing page to a similar looking document on another server. Since some image formats, such as Scalable Vector Graphics…

Certificate revocation service failure may cause Opera to show an unverified site as secure – Opera Security Advisories

Severity Moderate Description When accessing secure websites, Opera checks with a number of services to check if the website’s security certificate has been revoked. Normally, if Opera cannot check revocation status, it will not present the site as secure. In some cases, a failure in one of these services can cause Opera not to check…

Truncated dialogs may be used to trick users – Opera Security Advisories

Severity Low Description When an important dialog is being displayed, such as a download dialog, the entire dialog should be visible, so that the user can clearly see what the dialog’s buttons will do. In some cases, specific user interactions can cause Opera not to enforce this correctly, allowing the window to become smaller than…

Certain characters in HTML can incorrectly be ignored, which can facilitate XSS attacks – Opera Security Advisories

Severity High Description Sites that allow content to be provided by untrusted users, such as forums and blogging sites, typically sanitize the untrusted content to ensure that it does not contain any harmful content, such as malicious scripts. When certain characters appear at specific locations within HTML markup, they can cause Opera to ignore either…

Element HTML content can be incorrectly returned without escaping, bypassing some HTML sanitizers – Opera Security Advisories

Severity High Description When sites accept HTML from untrusted users, and use that HTML as page content, they typically sanitize the untrusted HTML to ensure that it does not contain any harmful content, such as malicious scripts. In some cases, this sanitization may be performed by writing and reading the contents of DOM elements. In…