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Deserialization Issues Also Affect .NET, Not Just Java (bleepingcomputer.com)
"The .NET ecosystem is affected by a similar flaw that has wreaked havoc among Java apps and developers in 2016," reports BleepingComputer. An anonymous reader writes:
The issue at hand is in how some .NET libraries deserialize JSON or XML data, doing it in a total unsecured way, but also how developers handle deserialization operations when working with libraries that offer optional secure systems to prevent deserialized data from accessing and running certain methods automatically. The issue is similar to a flaw known as Mad Gadget (or Java Apocalypse) that came to light in 2015 and 2016. The flaw rocked the Java ecosystem in 2016, as it affected the Java Commons Collection and 70 other Java libraries, and was even used to compromise PayPal's servers.
Organizations such as Apache, Oracle, Cisco, Red Hat, Jenkins, VMWare, IBM, Intel, Adobe, HP, and SolarWinds , all issued security patches to fix their products. The Java deserialization flaw was so dangerous that Google engineers banded together in their free time to repair open-source Java libraries and limit the flaw's reach, patching over 2,600 projects. Now a similar issue was discovered in .NET. This research has been presented at the Black Hat and DEF CON security conferences. On page 5 [of this PDF], researchers included reviews for all the .NET and Java apps they analyzed, pointing out which ones are safe and how developers should use them to avoid deserialization attacks when working with JSON data.
Organizations such as Apache, Oracle, Cisco, Red Hat, Jenkins, VMWare, IBM, Intel, Adobe, HP, and SolarWinds , all issued security patches to fix their products. The Java deserialization flaw was so dangerous that Google engineers banded together in their free time to repair open-source Java libraries and limit the flaw's reach, patching over 2,600 projects. Now a similar issue was discovered in .NET. This research has been presented at the Black Hat and DEF CON security conferences. On page 5 [of this PDF], researchers included reviews for all the .NET and Java apps they analyzed, pointing out which ones are safe and how developers should use them to avoid deserialization attacks when working with JSON data.
Real developers use an XML or JSON reader instead of using direct deserialization. Trust me I've built systems both ways and deserialization directly into objects is no bueno. You end up with more problems with version compatability alone to negate the benefits. There are also performance issues as well.
We'll make great pets
Completely agree. We used .net binary serialization/deserialization because it was such a quick way to get things up and running...with like two lines of code. The fact that the serialized objects were about 10x bigger than they needed to be was not a problem.
It turns out the namespaces are included in the serialized data, so the moment we did an ounce of lightweight refactoring we broke it. It took us less than a day to write our own serializer, but an extra three days of combined manpower to get a format converter built and deployed.
We would have saved all that if we had just started with our own serializer.
Prefab solutions to simple problems are a deal with the devil. Beware!
JSON or YAML are probably both fine. XML is simply wasteful and unnecessary. Personally I think we should be using something like s-expressions (lisp-like). People hate them because of the parens but every other encoding has as many negative points in different ways. The advantage is that the syntax is far simpler to understand and parse leading to safer software. Some might say that having an "executable" format is bad but I'd point to bugs like this as being proof that even "text" formats are just executables in disguise. The Lisp creed is "data is code" and I've come to agree.
XML is like violence. If it's not solving your problem, you're not using enough.
JSON only defines a bunch of basic data types. It defines no ability to run anything. These bugs are in (de)serialization layer above it, which uses JSON as a transport and extend the meaning of the data stored to be able to deserialize higher-level objects.
JSON or XML are not the problem here. The same problem could happen if you serialized to CSV or TXT or anything else for that matter.
The title is sensationalistic. Even the original bug the author talks about, calling it repeatedly a "Java" bug, was actually a bug in the Apache Commons Collections library, not in the platform, and it could only be triggered if a server using the library allowed customers to provide serialized data for itself to deserialize, which is severely wrong in the first place (it's akin to eval()-ing client-provided text).
I ask them questions about their courses in algorithms and what they did, and they say things like "we learned what the foundational algorithms are and how to compare their performance." Did you actually write a merge sort? "No, there's no need because every major language has that sort of thing built in."
Consider me a cultist follower of your hypothesis. 20 years in CS, the last 10 I have seen it take a sharp dive. The only explanation I have is the explosion over 15 years ago in OSS and that what you espouse is true: Everyone thinks they can develop or engineer, because the code is tied up in nice little solution blocks.
Need a sort algo? Just codeproject.com
Need some bi-directional comm between remotes? Just github.com...etc....
The number of people I have turned away in the first two days of testing, who could not even write a simple priority Q... its more than disheartening.
These are the "developers" who are supposed to code my future? Fuck me! I'll be working till I die.
The serialization format has nothing to do with the deserialization vulnarabilities.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
General rule of thumb as always... a vague security announcement is never as big a deal as its title makes it out to be.
There really isn't much of a problem. Reading TFA, a few vulnerabilities have been discovered in a couple applications and libraries. None of these were part of .NET, and no systemic issues in how people code for .NET have been found.