Sites can change framed content on other sites – Opera Security Advisories

Sites can change framed content on other sites – Opera Security Advisories OPCOM Team | December 16, 2008 Severity Highly Severe Problem Description Scripts are able to change the addresses of framed pages that come from the same site. Due to a flaw in the way that Opera checks what frames can be...

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...

History Search can be used to execute arbitrary code – Opera Security Advisories

History Search can be used to execute arbitrary code – Opera Security Advisories OPCOM Team | December 16, 2008 Severity Extremely Severe Problem Description When certain parameters are passed to Opera’s History Search, they can cause content not to be correctly sanitized. This can allow scripts ...

Java applets can be used to read sensitive information – Opera Security Advisories

Java applets can be used to read sensitive information – Opera Security Advisories OPCOM Team | December 16, 2008 Severity: Highly Severe Problem Description Once a Java applet has been cached, if a page can predict the cache path for that applet, it can load the applet from the cache, causing it...

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...

Images can be read cross-domain with canvas

HTML CANVAS elements can use images as patterns, and that image data is made available to scripts. When the images are retrieved from other Web sites, the image data should no longer be available to scripts. A flaw exists in the way that Opera checks for the source of these images. Suitable...

Opera not vulnerable to JPEG processing vulnerability in Microsoft’s GDI+ library – Opera Security Advisories

Opera not vulnerable to JPEG processing vulnerability in Microsoft’s GDI+ library – Opera Security Advisories OPCOM Team | February 9, 2007 Opera is not vulnerable to the JPEG processing vulnerability in Microsoft’s GDI+ library. Details: Microsoft Security Bulletin MS04-028 Buffer Overrun in JPE...

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...

A forged SSL server certificate can be accepted by Opera as a valid certificate – Opera Security Advisories

A forged SSL server certificate can be accepted by Opera as a valid certificate – Opera Security Advisories OPCOM Team | September 21, 2006 Summary: A forged SSL server certificate can be accepted by Opera as a valid certificate. Severity: Highly critical Vulnerable versions: Opera for desktop...

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...

Opera may execute command line embedded in URLs – Opera Security Advisories

Opera may execute command line embedded in URLs – Opera Security Advisories OPCOM Team | November 23, 2005 Summary Opera will execute command lines embedded in the URL when anotherprogram uses Opera to open a link. This affects UNIX versions ofOpera Linux/FreeBSD/Solaris. Severity: High Problem...

Data Privacy Day: Inside the role of Data Protection Officer at Opera

Privacy Data Privacy Day: Inside the role of Data Protection Officer at Opera Share January 28th, 2026 Privacy matters all year round. But every January, Data Privacy Day is a great opportunity to learn more about data privacy and protection, and to highlight their importance for everyone in the...

Protected with Opera Neon: Understanding agentic browser security

Security Protected with Opera Neon: Understanding agentic browser security Share October 21st, 2025 Hi Opera users, If you were hanging out around these parts in the past few weeks, you might have noticed that we launched Opera Neon – an AI agentic browser that can browse with you or for you, tak...

Update your browser: Security fixes for latest Chrome zero-day

News, Security Update your browser: Security fixes for latest Chrome zero-day Share June 5th, 2025 Hi everyone! The latest patches to the Opera, Opera GX, Opera Air, and Opera for Android address several recent vulnerabilities, including a zero-day exploit CVE-2025-5419. We recommend updating you...

Update your browser: Security fixes for latest Chrome zero-day

News, Security Update your browser: Security fixes for latest Chrome zero-day Share August 23rd, 2024 Hi everyone! The latest patches to the Opera and Opera GX address several recent vulnerabilities, including a zero-day exploit CVE-2024-7971. We recommend updating your browsers to the latest...

It’s Data Privacy Day: Here’s how to protect your data and become your own privacy champion

News, Security It’s Data Privacy Day: Here’s how to protect your data and become your own privacy champion Share January 27th, 2023 Hello readers! January 28 is Data Privacy Day – an annual celebration of all things data protection and online privacy! It’s an opportunity for businesses and users ...

Are you still using public Wi-Fi without a VPN?

Security Are you still using public Wi-Fi without a VPN? Share October 14th, 2022 Hi readers, October is Cybersecurity Awareness Month and the focus is on you, the user. All the privacy and security features in the world are worth nothing if we ourselves don’t apply some best practices to our...

Opera Privacy Statement Update 2022

Privacy Opera Privacy Statement Update 2022 Share August 29th, 2022 Opera, a browser company based out of Oslo, Norway, cares deeply about user security and data protection. With that in mind, we actively work on improving our internal practices and communications with you, our users. We are maki...

Opera’s Free Browser VPN Completes Independent Security Audit by Cure53

News Opera’s Free Browser VPN Completes Independent Security Audit by Cure53 Share March 30th, 2022 Today we’re happy to announce the completion of an independent security audit of Opera’s free built-in browser VPN. Opera’s free, no-log, built-in browser VPN was originally launched as part of the...

Can a browser extension be cursed?

Privacy Can a browser extension be cursed? Share December 4th, 2020 Mallory tries to create a browser extension that will let him spy on Alice. TL;DR: skip to the conclusions to see what Alice learned. The Privacy Problem Mallory was quite tired of his failed attempts to melt Alice’s heart. She...

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...

Opera becomes part of the CNA program

News Opera becomes part of the CNA program Share December 13th, 2019 Usually, Friday the 13th is considered to be an unlucky day. However, this is not the case for Opera, as we have great news, especially for security researchers and all security-minded Opera fans. We are proud to announce that...

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...

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...

New home for the Security Group blog

News New home for the Security Group blog Share October 31st, 2013 Welcome to the new home of the Opera Security Group. We have changed our blogging platform. For more more information regarding the switch, please see this post. If you received this blog post in your feed reader, you do not need ...

RC4 encryption protocol is vulnerable to certain brute force attacks – Opera Security Advisories

Weaknesses in the RC4 encryption protocol have been found, allowing an attacker to deduce the plaintext. If the same message is encrypted many millions of times, statistical methods can be used to extract valuable information, such as cookies. Due to the time this amount of requests takes, this i...

DOM events manipulation might be used to execute arbitrary code – Opera Security Advisories

DOM events manipulation might be used to execute arbitrary code – Opera Security Advisories OPCOM Team | January 29, 2013 Severity: High Description: Particular DOM event manipulations can cause Opera to crash. In some cases, this crash might occur in a way that allows execution of arbitrary code...

Use of SVG clipPaths can allow execution of arbitrary code – Opera Security Advisories

When SVG documents with specifically prepared clipPaths are used in Opera, Opera may allow other content to overwrite the memory, before referencing the memory, which will lead to a crash. If an attacker can control the contents being written into memory, execution of arbitrary code may occur...

Private data can be disclosed to other computer users, or be modified by them – Opera Security Advisories

Private data such as cache, password files, and Opera’s configuration files are supposed to be visible only to the user who owns the Opera profile. Opera does not set the profile folder permissions correctly, allowing other computer users to read the sensitive contents of profile files. In some...

Malformed GIF images could allow execution of arbitrary code – Opera Security Advisories

When loading GIF images into memory, Opera should allocate the correct amount of memory to store that image. Specially crafted image files can cause Opera to allocate the wrong amount of memory. Subsequent data may then overwrite unrelated memory with attacker-controlled data. This can lead to a...

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

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...

Plug-in content may monitor keystrokes on unrelated pages – Opera Security Advisories

Plug-ins may use operating system features to detect key presses when the plug-in is focused. If the plug-in does not detect its own focused state correctly, it can detect key presses when other pages are focused, allowing the plug-in content to detect key presses intended for pages from other...

Certain URL constructs can allow arbitrary code execution – Opera Security Advisories

Certain page address URL constructs can cause Opera to allocate the wrong amount of memory for storing the address. When it then attempts to store the address, it will overwrite unrelated memory with attacker-controlled data. This can lead to a crash, which may also execute that data as code...

Carefully timed reloads, redirects, and navigation can spoof the address field – Opera Security Advisories

The address field should always show the address of the page that is being displayed. Certain types of navigation, combined with reloads and redirects to a slowly-responding target site can cause the address field to show the target site’s address, while the attacking site is still being displaye...

Overlapping content can trick users into executing downloads – Opera Security Advisories

Dialogs such as the download dialog are usually displayed on top of page content, to ensure that the user knows that the dialog is requesting attention. In some cases, this policy was not implemented correctly in Opera, allowing certain page content to overlay the dialog. In these cases, clicking...

Carefully timed reloads and redirects can spoof the address field – Opera Security Advisories

The address field should always show the address of the page that is being displayed. In certain cases, if a target site responds slowly, reloading an attacking page and redirecting to the target page can cause the address field to show the target site’s address, while the attacking site is still...

Changing from a single-user to a multi-user installation on Windows (rev2) – Opera Security Advisories

Changing from a single-user to a multi-user installation on Windows rev2 – Opera Security Advisories OPCOM Team | January 5, 2012 If you received the error message “There was a problem initializing Opera Mail. Engine Init Failed”, it may mean that you have a stand-alone USB installation of Opera...

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...

Clickjacking attacks may be carried out against internal opera: URLs – Opera Security Advisories

Clickjacking attacks may be carried out against internal opera: URLs – Opera Security Advisories OPCOM Team | January 25, 2011 Severity High Description Internal opera: URLs which may be used to modify the Opera configuration have some intentional restrictions that are designed to mitigate possib...

Web pages can gain limited access to files on the user’s computer – Opera Security Advisories

Web pages can gain limited access to files on the user’s computer – Opera Security Advisories OPCOM Team | January 25, 2011 Severity High Description Certain types of HTTP responses and redirections can cause Opera to mistakenly give elevated privileges to remote web pages. These pages can then u...

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...

Error messages can leak onto unrelated sites – Opera Security Advisories

Scripting error messages are normally available only to the page that caused the error. In some cases, the error messages could be passed to other sites as the contents of unrelated variables, and may contain sensitive information. If those sites write the content into the page markup, this could...

Web fonts can be used to spoof the page address – Opera Security Advisories

In some cases, a Web font intended to be used for page content could be incorrectly used by Opera to render parts of the user interface, including the address field. This can be used by a malicious site to display a false domain name in the address field...

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...

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...

Long hostnames in file: URLs can cause execution of arbitrary code

Exceptionally long host names in file: URLs can cause a buffer overflow, which may be exploited to execute arbitrary code. Remote Web pages cannot refer to file: URLs, so successful exploitation involves tricking users into manually opening the exploit URL, or a local file that refers to it...

Certain characters can obscure the page address – Opera Security Advisories

Certain characters can obscure the page address – Opera Security Advisories OPCOM Team | June 9, 2008 Severity: Less Severe Problem Description When a page address contains certain characters, they can cause the page address text to be misplaced. In some cases, this could make characters be...

Vulnerability in Opera’s use of kfmclient – Opera Security Advisories

Vulnerability in Opera’s use of kfmclient – Opera Security Advisories OPCOM Team | February 9, 2007 Severity: Moderate Since version 7.50, Opera for Linux has offered theuser a new way to open files which Opera can not openitself: “Open with kfmclient”. This feature can beexploited to run malicio...

Opera for Android has received Google Play’s Independent Security Review badge. Here’s what this means for your security

Security Opera for Android has received Google Play’s Independent Security Review badge. Here’s what this means for your security Share January 30th, 2025 Hey Opera users! You might have seen that Opera for Android has achieved a new security-focused milestone: If you search for Opera for Android...