Sites using revoked intermediate certificates might be shown as secure – Opera Security Advisories

Sites using revoked intermediate certificates might be shown as secure – Opera Security Advisories OPCOM Team | August 29, 2009 Summary Opera does not check the revocation status for intermediate certificates not served by the server. If the intermediate is revoked, this might not impact the...

The links panel can allow cross-site scripting – Opera Security Advisories

The links panel can allow cross-site scripting – Opera Security Advisories OPCOM Team | December 16, 2008 Severity Highly Severe Problem Description The links panel shows links in all frames on the current page, including links with JavaScript URLs. When a page is held in a frame, the script is...

Feed links can link to local files – Opera Security Advisories

Feed links can link to local files – Opera Security Advisories OPCOM Team | December 16, 2008 Severity Less Severe Problem Description As a security precaution, Opera does not allow Web pages to link to files on the user’s local disk. However, a flaw exists that allows Web pages to link to feed...

Registering Opera as a protocol handler can allow it to be used to execute arbitrary code – Opera Security Advisories

Registering Opera as a protocol handler can allow it to be used to execute arbitrary code – Opera Security Advisories OPCOM Team | December 16, 2008 Severity Extremely Severe Problem Description When an application attempts to access a URL that uses a protocol that it does not understand, it may...

Pages held in frames are able to change the location of pages in unrelated frames on the parent page – Opera Security Advisories

Pages held in frames are able to change the location of pages in unrelated frames on the parent page – Opera Security Advisories OPCOM Team | June 11, 2008 Severity: Less Severe Problem Description: Pages from different sources held on the same parent page should not be able to modify the locatio...

Very large link addresses can cause Opera to crash – Opera Security Advisories

Very large link addresses can cause Opera to crash – Opera Security Advisories OPCOM Team | October 17, 2006 Summary: Very large link addresses can cause Opera to crash. Severity: Moderate Problem description An extremely long link address can cause Opera to crash.A specially crafted long link...

The link tooltip and the statusbar can be misleading – Opera Security Advisories

The link tooltip and the statusbar can be misleading – Opera Security Advisories OPCOM Team | February 17, 2006 Summary Opera’s status bar shows the “title” attribute of a form inputimage, not the form’s “action” URL. This may mislead the user. Severity: Very low Problem description It is possibl...

What is the TLS padlock saying?

Security What is the TLS padlock saying? Share November 20th, 2020 Alice and Bob use TLS to keep their long distance relationship hot and private. TL;DR: skip to the conclusions to see what Alice learned. The Privacy Problem Alice and Bob had to turn their relationship into a long distance one...

Opera Receives DevSecOps All-Star Award at SnykCon 2020

News Opera Receives DevSecOps All-Star Award at SnykCon 2020 Share October 28th, 2020 AtSnykCon 2020, Opera received the DevSecOps All-Star Award for leveraging Snyk to bring a complete and fully automated DevSecOps process into a secure software development lifecycle. Opera was represented by...

Thanks to the researchers 2017

Research Thanks to the researchers 2017 Share March 3rd, 2017 We would like to thank the researchers who have offered us their assistance throughout the year, to help enhance the security of our websites. Special mention goes to those who discover and report security issues: Johnny Nipper Mehmet...

Opera 12 and Opera Mail security update

Security Opera 12 and Opera Mail security update Share February 16th, 2016 We realize that those of you on old operating systems like Windows XP SP1 and older are left without much choice beyond using our Presto-based browser. With security standards on the web changing so much we didn’t want to...

Security changes in Opera 25; the poodle attacks

Security Security changes in Opera 25; the poodle attacks Share October 15th, 2014 So the last weeks have been rather hectic behind the scenes in the browser security world, when Google security group found a new way to exploit a rather well known design weakness in SSLv3 published in the paper...

Possibly Tricking Users – The Perils of Drag n Drop Decadence

Security Possibly Tricking Users – The Perils of Drag n Drop Decadence Share May 12th, 2014 In the recent Opera 21 Stable release, we fixed a number of bugs relating to the address field. Normally, we would not want to give away too much about a security issue, as it would give a potential attack...

Carefully timed redirects can allow cross site scripting – Opera Security Advisories

Scripts on a page are supposed to be restricted so that they can only interact with other pages from the same domain and security context. Carefully timed redirects can cause scripts to execute in the wrong security context in Opera. This allows cross site scripting XSS...

Issue with error pages can cause a system crash – Opera Security Advisories

When attempting to resolve a URL which cannot be interpreted as a legal URL, Opera will create an error page to display to the user when they load it. If enough invalid URLs can be created, Opera can use up all available disk space with these error pages, causing the browser or operating system t...

Data URIs may be used to initiate cross site scripting against unrelated sites – Opera Security Advisories

Data URIs are supposed to inherit the security context from the page that created them. In some cases, Opera does not enforce this correctly, and will allow unrelated data URIs to interact both with each other, and their source pages. This can be used to enable cross site scripting against the...

Manipulating the window can be used to spoof the page address – Opera Security Advisories

Manipulating the window can be used to spoof the page address – Opera Security Advisories OPCOM Team | October 6, 2010 Severity Low Description Web page scripts can be used to alter the size of the browser window. In some cases, this manipulation can cause the wrong part of the Web page address t...

Data URIs can be used to allow cross-site scripting – Opera Security Advisories

Data URIs can be used to allow cross-site scripting – Opera Security Advisories OPCOM Team | June 22, 2010 Severity Highly severe Description Data URIs are allowed to run scripts that manipulate pages from the site that directly opened them. In some cases, the opening site is not correctly...

Script injection in feed preview can reveal contents of unrelated news feeds – Opera Security Advisories

Script injection in feed preview can reveal contents of unrelated news feeds – Opera Security Advisories OPCOM Team | December 15, 2008 Severity Highly Severe Problem Description When Opera is previewing a news feed, some scripted URLs are not correctly blocked. These can execute scripts which ar...

Opera asks for my keychain password on macOS – what do I do? Opera 53 has a new signing certificate

Security Opera asks for my keychain password on macOS – what do I do? Opera 53 has a new signing certificate Share May 30th, 2018 Hello, We would like to let you know that we have updated our software signing certificate from Opera Software ASA to Opera Software AS. This is why your macOS is aski...

Upcoming update with IDN homograph phishing fix

Security Upcoming update with IDN homograph phishing fix Share April 21st, 2017 Domains are an integral part of the internet. Similar to how people write different languages using different characters or scripts, domain names can be composed of various scripts in whole or in part, and are called...

Opera installer mistakenly marked as malicious

Security Opera installer mistakenly marked as malicious Share February 22nd, 2017 During the past few days some of our users have contacted us raising the concern that the Qihoo 360 Total Security anti-virus software has been labelling the Opera installer executable for Windows as some form of...

Legacy Opera Presto source code appearance in online sharing sites

Security Legacy Opera Presto source code appearance in online sharing sites Share January 18th, 2017 Opera recently became aware that source code from our legacy browser engine, Presto, has appeared in some online code and file sharing sites. This code is the property of Opera Software and has be...

Optimizing encrypted video

Security Optimizing encrypted video Share February 25th, 2015 You might have seen our press release that Opera’s Rocket Optimizer can now optimize encrypted video streams. The attentive reader will already have halted and said, “wait, what?”. In this blog post, we’ll explain how this works. Rocke...

Security changes in Opera 20 update

Security Security changes in Opera 20 update Share March 13th, 2014 We have just released a silent update of Opera 20, you would most likely not even have noticed. From a security perspective, we have made two interesting changes in this update. The first one regards what we call the badge, the...

Printing issue can allow data leaks to other system users, or allow them to corrupt data – Opera Security Advisories

When pages are printed by Opera, a temporary file is created, which contains the document to print. This document is not created with the correct permissions, allowing other users of the system to read its contents. When printed with certain popular printing frameworks, an additional temporary fi...

Large form inputs can allow execution of arbitrary code – Opera Security Advisories

Large form inputs can allow execution of arbitrary code – Opera Security Advisories OPCOM Team | January 25, 2011 Severity Critical Description When certain large form inputs appear on a web page, they can cause Opera to crash. In some cases, the crash can lead to memory corruption, which could b...

JavaScript might run in the wrong context if loaded from error page – Opera Security Advisories

JavaScript might run in the wrong context if loaded from error page – Opera Security Advisories OPCOM Team | October 11, 2010 Severity Moderate Description If Opera is sent to an invalid URL, an error page will be displayed along with a link to the URL. The URL linked to might run scripts, and in...

Specially crafted JPEG images can be used to execute arbitrary code – Opera Security Advisories

Specially crafted JPEG images can be used to execute arbitrary code – Opera Security Advisories OPCOM Team | February 25, 2009 Severity Extremely Severe Problem Description Specially crafted JPEG images can cause Opera to corrupt memory and crash. Successful exploitation can lead to execution of...

Certain characters can be used to allow cross-site scripting – Opera Security Advisories

Certain characters can be used to allow cross-site scripting – Opera Security Advisories OPCOM Team | December 17, 2008 Severity Highly Severe Problem Description When accepting HTML content from untrusted users, Web sites sometimes employ some kind of filtering to ensure that the content cannot...

Feed preview can reveal contents of unrelated news feeds – Opera Security Advisories

Feed preview can reveal contents of unrelated news feeds – Opera Security Advisories OPCOM Team | December 16, 2008 Severity Highly Severe Platforms All desktop versions Problem Description When Opera is previewing a news feed, some scripts are not correctly blocked. These scripts are able to...

Simulated text inputs can trick users into uploading arbitrary files – Opera Security Advisories

Simulated text inputs can trick users into uploading arbitrary files – Opera Security Advisories OPCOM Team | December 16, 2008 Severity: Moderately Severe Problem Description When a user types into a file input, scripts can cause some of the keystrokes to be ignored. If the script can convince t...

Custom shortcuts can pass the wrong parameters to applications – Opera Security Advisories

Custom shortcuts can pass the wrong parameters to applications – Opera Security Advisories OPCOM Team | December 16, 2008 Severity Moderately Severe Problem Description Custom shortcut and menu commands can be used to activate external applications. In some cases, the parameters passed to these...

A JPEG image with a malformed header can crash Opera – Opera Security Advisories

A JPEG image with a malformed header can crash Opera – Opera Security Advisories OPCOM Team | December 16, 2008 Summary A JPEG image with a malformed header can crash Opera, and causearbitrary code to be run. Severity Moderate Problem description A specially crafted DHT marker in the JPEG file...

Fuzzing HTTP Proxies: Squid, Part 2

Research Fuzzing HTTP Proxies: Squid, Part 2 Share October 1st, 2021 Security is important to us, here at Opera. That’s why, apart from making our browsers safer, we also want to make the Web a bit safer. One of those ways is helping other developers find and fix vulnerabilities in their products...

Update your browser regularly

Security Update your browser regularly Share February 12th, 2021 Mallory tries to hack an OS in order to spy on Alice. TL;DR: skip to the conclusions to see what Alice learned. Update your browser regularly Every once in a while you’re asked to update the software on your computer, or just told...

Security changes and features of Opera 19

Security Security changes and features of Opera 19 Share January 31st, 2014 Opera 19 is now been put through its paces on the Developer and Next channels, and is now out on the Stable channel. Opera 19 for Android has also recently been released. New features As with every release, each new featu...

Thanks to the researchers 2014

Research Thanks to the researchers 2014 Share January 31st, 2014 Each year, a number of researchers offer their assistance to help us tighten the security of our wide array of websites. We would like to take this opportunity to thank the researchers and testers of 2014 for their assistance in...

Pages can prevent navigation to a target page, spoofing the address field – Opera Security Advisories

When a user types a new URL for the browser to load, the currently active page may detect when the new page is about to load and prevent the navigation, while still leaving the new URL displayed in the address bar. This can then be used to spoof the URL of the target page. The malicious page woul...

WAP form content can be leaked to other sites – Opera Security Advisories

When accepting user input in form fields on a WAP page, WML requires that the input contents are remembered, and used to populate every further input sharing the same name. This should continue as long as the user continues to click links known as a WAP session, even populating similarly named...

Making browsing safe from phishing

Privacy, Security Making browsing safe from phishing Share January 7th, 2021 Mallory tries to create a phishing site to lure Alice into revealing her secrets. TL;DR: skip to the conclusions to see what Alice learned. The Privacy Problem In the previous episode, Mallory was thinking about...

Thanks to the researchers 2018

News Thanks to the researchers 2018 Share February 13th, 2018 Every year, researchers offer us their assistance to help enhance the security of our websites. We would like to thank those who discovered and reported security issues in 2018. EDIT: The list of researchers was moved to our new site,t...

Opera bug bounty: How vulnerability research is evolving with AI

Security Opera bug bounty: How vulnerability research is evolving with AI Share August 28th, 2026 Hi Opera users! Browser security is constantly evolving, and so are the ways vulnerabilities are discovered. At Opera, we heavily invest in securing our products and services through the efforts of o...