Opera before 11.62 does not ensure that a dialog window is placed on top of content windows, which makes it easier for user-assisted remote attackers to trick users into downloading and executing arbitrary files via a download dialog located under other windows.

Opera before 11.62 allows user-assisted remote attackers to trick users into downloading and executing arbitrary files via a small window for the download dialog.

Multiple integer overflows in Opera 11.60 and earlier allow remote attackers to cause a denial of service (application crash) via a large integer argument to the (1) Int32Array, (2) Float32Array, (3) Float64Array, (4) Uint32Array, (5) Int16Array, or (6) ArrayBuffer function. NOTE: the vendor reportedly characterizes this as "a stability issue, not a security issue."

Opera 11.60 and earlier does not prevent capture of data about the times of Same Origin Policy violations during IFRAME loading attempts, which makes it easier for remote attackers to determine whether a document exists in the browser cache via crafted JavaScript code.

Opera before 11.51 allows remote attackers to cause an insecure site to appear secure or trusted via unspecified actions related to Extended Validation and loading content from trusted sources in an unspecified sequence that causes the address field and page information dialog to contain security information based on the trusted site, instead of the insecure site.

Opera cannot properly restrict modifications to cookies established in HTTPS sessions, which allows man-in-the-middle attackers to overwrite or delete arbitrary cookies via a Set-Cookie header in an HTTP response, related to lack of the HTTP Strict Transport Security (HSTS) includeSubDomains feature, aka a "cookie forcing" issue.

Unspecified vulnerability in Opera before 11.11 allows remote attackers to cause a denial of service (application crash) via vectors involving a Certificate Revocation List (CRL) file, as demonstrated by the multicert-ca-02.crl file.

Opera before 11.11 does not properly handle destruction of a Silverlight instance, which allows remote attackers to cause a denial of service (application crash) via a web page, as demonstrated by vod.onet.pl.

The Cascading Style Sheets (CSS) implementation in Opera before 11.11 does not properly handle the column-count property, which allows remote attackers to cause a denial of service (infinite repaint loop and application hang) via a web page, as demonstrated by an unspecified Wikipedia page.

Opera before 11.11 allows user-assisted remote attackers to cause a denial of service (application crash) via a crafted web page that is not properly handled during a reload occurring after the opening of a popup of the Easy Sticky Note extension.

Unspecified vulnerability in Opera before 11.11 allows remote attackers to cause a denial of service (application crash) via unknown content on a web page, as demonstrated by www.falk.de.

Opera before 11.11 does not properly implement FRAMESET elements, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via vectors related to page unload.

The VEGAOpBitmap::AddLine function in Opera before 10.61 does not properly initialize memory during processing of the SIZE attribute of a SELECT element, which allows remote attackers to trigger an invalid memory write operation, and consequently cause a denial of service (application crash) or possibly execute arbitrary code, via a large integer attribute value.

Opera before 11.01 does not properly implement Wireless Application Protocol (WAP) dropdown lists, which allows user-assisted remote attackers to cause a denial of service (application crash) via a crafted WAP document.

Unspecified vulnerability in Opera before 11.01 allows remote attackers to cause a denial of service (application crash) via unknown content on a web page, as demonstrated by vkontakte.ru.

The Delete Private Data feature in Opera before 11.01 does not properly implement the "Clear all email account passwords" option, which might allow physically proximate attackers to access an e-mail account via an unattended workstation.

Opera before 11.01 does not properly handle redirections and unspecified other HTTP responses, which allows remote web servers to obtain sufficient access to local files to use these files as page resources, and consequently obtain potentially sensitive information from the contents of the files, via an unknown response manipulation.

Opera before 11.01 does not properly restrict the use of opera: URLs, which makes it easier for remote attackers to conduct clickjacking attacks via a crafted web site.

Integer truncation error in opera.dll in Opera before 11.01 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via an HTML form with a select element that contains a large number of children.

The Cascading Style Sheets (CSS) Extensions for XML implementation in Opera before 11.01 recognizes links to javascript: URLs in the -o-link property, which makes it easier for remote attackers to bypass CSS filtering via a crafted URL.