I browse to an html page with an applet tag. The applet tag refernces two signed jars. I receive two Security Warning dialogs indicating the revocation status cannot be checked, accept the risk, and click Run for both of them. The browser displays an error gif that says "Error: click for details. I click.
The Application Error dialog says ClassNotFoundException and the name of the class, and displays three options. I click (1) Details and see the Java Console with the menu but no errors. I click (2) Ignore with no apparent effect. I click (3) reload and the applet loads and runs properly.
I have the latest java security update. This happens in Chrome and FireFox. I've signed the certificate using a Certificate from my Acitve Directory Certificate Server, I added the site to my list of trusted sites, and the CA certificate to the list of CA certs in the Java Control panel.
I'm glad it works in the end but would like to avoid having to click Reload each time. Can anyone suggest what I might do differently?
General suggestion is to not use what is all but a completely deprecated technology (applets).
More specifically, it is likely a browser problem in how the JVM and class-loader is working with signed JARs. Initially it would not load because it could not find/verify a registry for certificate revocations. So the class did not load. On re-load, it picked up on the 'ignore' the issue problem so it then loaded the class.
This seems related to a similar question that suggests verifying file-naming as well: ClassNotFoundException only if JAR is signed
Related
I have been trying to create a self-signed jar. I have embedded it on a website. However (this may be a Windows-specific problem), when the applet loads, this pops up:
"Your security settings have blocked a self-signed application from running."
According to every scrap of documentation I can get my hands on, I am supposed to be prompted as to whether or not I want to trust this application.
This is embedded in GameJolt's website, so there is no HTML code to be posted.
My META-INF folder contains a .MF, .SF, and .DSA file.
Do I need anything else?
According to every scrap of documentation I can get my hands on, I am supposed to be prompted as to whether or not I want to trust this application.
You must be getting old scraps. In recent times, Oracle decided to raise the security level so self-signed apps. were no longer acceptable.
I have some issues while using some applet in my application. It's showing that i have untrusted applet, that my jar files are not allowed to be run, showing that they are also using an old version of java (I'm using java 1.7).
Do you have any solution, like maybe using a third-pary certificate ?
Anyway, thanks for your help.
Check if this helps. You will see more details here
Setting the Security levels through the Java Control Panel
In the Java Control Panel, click on the Security tab.
Select the desired Security level.
Click Apply.
Click OK to save changes made to the Java Control Panel.
Security levels in the Java Control Panel
Very High
This is the most restrictive security level setting. All the applications that are signed with a valid certificate and include the Permissions attribute in the manifest for the main JAR file are allowed to run with security prompts. All other applications are blocked.
High
This is the minimum recommended (and default) security level setting. Applications that are signed with a valid or expired certificate and include the Permissions attribute in the manifest for the main JAR file are allowed to run with security prompts. Applications are also allowed to run with security prompts when the revocation status of the certificate cannot be checked. All other applications are blocked.
Medium (removed from Java 8 Update 20 and later versions)
Only unsigned applications that request all permissions are blocked. All other applications are allowed to run with security prompts. Selecting the Medium security level is not recommended and will make your computer more vulnerable should you run a malicious application.
The part of "Resolution" in that website said.
"Since the issue is being reported by the Java software or the Java plugin in the browser, there is nothing we can do to directly resolve the issue.
There are several workarounds possible, depending on how the site deals with browser security issues.
The most secure approach is to allow the applet to be run each time you are prompted.
If using Internet Explorer, click the [Run] button on the security warning popup window.
If using Firefox, two actions may be needed. First if the warning "This connection is untrusted" is displayed, click the "I Understand the Risks""
I have a small company with website, that I'd like to make more interesting by adding there applet. I've prepared it already, and when launched from eclipse it works correctly. However when it is launched as an applet, from website I have a warning that it is not trusted and cannot run it without adding my page to java exceptions.
And here the fun begins. I'd like to have my applet signed in order to allow customers use it without any changes in their java configuration. I'm not planning to make more applets, or any other code that would need signing, so I don't really need to buy expensive certificates.
I've tried self-signing, however according to Java 7 policies it is not enough to run an applet.
I've also wanted to obtain free OpenSource Code certificate from Certum.eu, however the link doesn't work anymore.
CACert is also not an option, as I've heard that it is not trusted in all browsers...
Is there any way I could sign my applet with no harm to my wallet?
The closest thing to an open source certificate is CACert which is however not supported in all browsers. Thawte and Certum seem to have stopped offering free certificates for open source projects. (If you really want to know write an email to Certum why the link is dead)
The only thing I know of currently is GlobalSign.
When i visit a java application running website I get error "application blocked by security settings" This is due to certificate problem. I know the publisher so i can trust him.
Then after a quick google search I changed security setting of java to medium and also added the website to Execption website list. Still I am getting a different window asking me to accept risk and continue running application(Shown in image below). This window comes every time i run it. So how it can be avoided?
For an application that was signed by a legitimate code signing certificate (that itself was signed by a proper certificate authority in Java's web of trust), you will still see the above dialog, but without the red text. It will display the name on the certificate, and you will have a checkbox that allows you to automatically trust all apps from the same vendor, thus avoiding seeing the dialog again.
However, when the application was not legitimately signed, you will see the above dialog even on medium setting, but you can run it by "accepting the risk". On default security level, you may not even have the option to "accept the risk" and proceed, and on "very high", you will definitely not have the option to proceed.
In order to avoid the dialog with the warning, the application will need to be signed. If it's signed by a legitimate code-singing certificate, it will behave as I described in the first paragraph. If it's self-signed, then the vendor will have to supply you with a copy of the root certificate they used to sign it, and you'll have to import the certificate into Java's store. Then, it will behave just like one that was legitimately signed.
I am trying to run my applet in a browser, chrome/IE but I get the following message:
Your security settings have blocked a local application from running
Due to Oracle, changing security level in java control panel from high to medium will solve the issue, but it does not. I have even tried the low level, and custom level too enabling all applications to run without any prompt. I have also changed the advanced setting to allow unsigned applets to run.
It does not work in any way.
Any help is appreciated.
Do the following
Go to IE
Tools -> Internet Options
Go to the Advanced Tab
Under Java(Sun) Select the check box saying 'Use JRE ... for applet' (requires restart)
Select Apply/Ok. Restart IE and try loading the applet again.
You can either make sure that the applet is signed by a valid cert, and it is not a self-signed cert. Or if you just want to bypass the warning, you can add the domain address to Exception Site List.
Java Control Panel -> Security tab -> Exception Site List
and also you may also try to add the website to the Trusted Zone in your IE if you are sure that the website is safe. In Trusted Zone, there are fewer restrictions to block you from running applet and running the out-of-date ActiveX.