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Threat Intelligence

7/29/2019
09:00 AM

9 Things That Don't Worry You Today (But Should)

There are security concerns that go far beyond the usual suspects. Here are some that should be on your list of scary things.
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ZIP Bombs
Since 1989, computer users have been taking advantage of Phil Katz's work in compression to reduce file sizes by as much as 1,032 to 1. The ZIP format is a common and critical component of file transfer in the enterprise, but the qualities that make it valuable can be used against an unwary recipient.
The 1,032 to 1 compression ratio is possible with DEFLATE, the compression algorithm used in most ZIPpers since the early 1990s. But by using other compression algorithms or techniques, much greater compression can be achieved. In a recent example, researcher David Fifield demonstrated a compression ratio of more than 28 million to 1,  resulting in a 46MB ZIP file that decompresses to approximately 4.5PB of data.
Fifield has created code producing an even larger ZIP bomb, a 2.9GB file that unzips to 2*64 +11727895877 bytes, a data size expressed in zettabytes (two orders of magnitude beyond petabytes).
These very large ZIP bombs have, so far, been confined to research activities, but it's not hard to imagine a threat actor using the technique to perform a denial-of-service attack against the storage and computation resources of a company.
(Image Source: FrankBoston via Adobe Stock)

ZIP Bombs

Since 1989, computer users have been taking advantage of Phil Katz's work in compression to reduce file sizes by as much as 1,032 to 1. The ZIP format is a common and critical component of file transfer in the enterprise, but the qualities that make it valuable can be used against an unwary recipient.

The 1,032 to 1 compression ratio is possible with DEFLATE, the compression algorithm used in most ZIPpers since the early 1990s. But by using other compression algorithms or techniques, much greater compression can be achieved. In a recent example, researcher David Fifield demonstrated a compression ratio of more than 28 million to 1, resulting in a 46MB ZIP file that decompresses to approximately 4.5PB of data.

Fifield has created code producing an even larger ZIP bomb, a 2.9GB file that unzips to 2*64 +11727895877 bytes, a data size expressed in zettabytes (two orders of magnitude beyond petabytes).

These very large ZIP bombs have, so far, been confined to research activities, but it's not hard to imagine a threat actor using the technique to perform a denial-of-service attack against the storage and computation resources of a company.

(Image Source: FrankBoston via Adobe Stock)

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edshawn61
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edshawn61,
User Rank: Apprentice
7/29/2019 | 6:43:43 PM
Great job
Your take on this topic is very interesting!
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