Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Perimeter

11/10/2009
10:00 AM
Adrian Lane
Adrian Lane
Commentary
50%
50%

Cell-Level Encryption

A friend of mine was wondering why cell-level encryption isn't used often in databases. What would seem to be a fast and efficient approach to data security actually requires a complex implementation. Cell-level encryption stands in stark contrast to commonly adopted transparent forms of database encryption, and helps us identify hidden costs and complexity.

A friend of mine was wondering why cell-level encryption isn't used often in databases. What would seem to be a fast and efficient approach to data security actually requires a complex implementation. Cell-level encryption stands in stark contrast to commonly adopted transparent forms of database encryption, and helps us identify hidden costs and complexity.Cell-based encryption is when you encrypt a single element within a single row of a database table. While it is considered database encryption, most commonly the encryption is performed outside of the database, from within the calling application. Sensitive data elements are encrypted before being inserted or updated.

The process of introducing encryption into an application is a fairly complex endeavor, requiring changes to the application logic, the addition of the cryptographic services, and assumption of key management tasks. You must additionally alter the database structure to store the encrypted strings, and alter any database queries that selected/used the now-encrypted data. The approach is very flexible, enabling you to encrypt pretty much any or all data. It also can be very secure, but the sheer amount of effort to make this work scares most people off.

Another misconception about cell-level encryption is it's faster because you encrypt less data. In practice, this is not correct. First, if you have sensitive data, then very seldom is it only a single row you are protecting. For example, if you have credit card numbers, then odds are you have one in every row of the table. Second, if you are running queries against encrypted data, then it is faster to decrypt that data as a whole column or table than row by row or element by element -- a lot faster. Technologies that work at the object level are more efficient in general-use cases and a heck of a lot simpler to implement.

Discussing cell encryption is mostly helpful in spotlighting the difficulties in encrypting database content at the application level. It is for these reasons, as well as a few others, that most people are moving to transparent forms of encryption.

In my next two posts, I'll discuss the two major forms of transparent encryption: file/folder and database transparent encryption. I want to clear up some of the confusion surrounding these technology approaches, delving into the business problems they solve, as well as the pitfalls around implementation and performance.

Adrian Lane is an analyst/CTO with Securosis LLC, an independent security consulting practice. Special to Dark Reading. Adrian Lane is a Security Strategist and brings over 25 years of industry experience to the Securosis team, much of it at the executive level. Adrian specializes in database security, data security, and secure software development. With experience at Ingres, Oracle, and ... View Full Bio

 

Recommended Reading:

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 7/6/2020
Ripple20 Threatens Increasingly Connected Medical Devices
Kelly Sheridan, Staff Editor, Dark Reading,  6/30/2020
DDoS Attacks Jump 542% from Q4 2019 to Q1 2020
Dark Reading Staff 6/30/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
How Cybersecurity Incident Response Programs Work (and Why Some Don't)
This Tech Digest takes a look at the vital role cybersecurity incident response (IR) plays in managing cyber-risk within organizations. Download the Tech Digest today to find out how well-planned IR programs can detect intrusions, contain breaches, and help an organization restore normal operations.
Flash Poll
The Threat from the Internetand What Your Organization Can Do About It
The Threat from the Internetand What Your Organization Can Do About It
This report describes some of the latest attacks and threats emanating from the Internet, as well as advice and tips on how your organization can mitigate those threats before they affect your business. Download it today!
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-15570
PUBLISHED: 2020-07-06
The parse_report() function in whoopsie.c in Whoopsie through 0.2.69 mishandles memory allocation failures, which allows an attacker to cause a denial of service via a malformed crash file.
CVE-2020-15569
PUBLISHED: 2020-07-06
PlayerGeneric.cpp in MilkyTracker through 1.02.00 has a use-after-free in the PlayerGeneric destructor.
CVE-2020-7690
PUBLISHED: 2020-07-06
It's possible to inject JavaScript code via the html method.
CVE-2020-7691
PUBLISHED: 2020-07-06
It's possible to use <<script>script> in order to go over the filtering regex.
CVE-2020-15562
PUBLISHED: 2020-07-06
An issue was discovered in Roundcube Webmail before 1.2.11, 1.3.x before 1.3.14, and 1.4.x before 1.4.7. It allows XSS via a crafted HTML e-mail message, as demonstrated by a JavaScript payload in the xmlns (aka XML namespace) attribute of a HEAD element when an SVG element exists.