Vulnerabilities / Threats // Insider Threats
2/21/2011
09:14 PM
Connect Directly
RSS
E-Mail
50%
50%

SSDs Prove Tough To Erase

Techniques that reliably erase hard disk drives don't produce the same results for solid state drives, warn University of California at San Diego researchers.

Solid state drives (SSDs) have a small security problem: they're tough to erase.

That warning comes from researchers at the University of California at San Diego. "Sanitization is well-understood for traditional magnetic storage, such as hard drives and tapes," said the researchers' in their study summary. "Newer solid state disks, however, have a much different internal architecture, so it is unclear whether what has worked on magnetic media will work on SSDs as well."

Accordingly, the researchers tried 14 different file sanitizing techniques -- ranging from Gutman's 35-pass method to the Schneier 7-pass method -- on SSDs. To study each technique's effectiveness, the researchers didn't query the flash translation layer (FTL) that's part of an SSD, but rather accessed the chips at the lowest level possible, via their pins. (Dismantling chips is straightforward, they said.)

What they found is that every data-erasing technique left at least 10MB of recoverable data from a 100MB file. Some techniques, such as overwriting the chip with pseudorandom data or using a British HMG IS5 baseline, left nearly all data intact.

By any measure, SSDs aren't the dominant way of storing data today, but their use is increasing. According to the recent InformationWeek Analytics State of Enterprise Storage Survey, nearly one-quarter of organizations have deployed SSDs in their data center, and more than half plan to either initiate or increase their use of SSDs this year.

Meanwhile, storage market researcher iSuppli predicts that the SSD penetration rate for laptops will increase from roughly 2% in 2010 to nearly 8% by 2014.

But according to the University of California at San Diego researchers, businesses must beware how they handle SSDs, because it's tough to erase data from them. "Our results show that naïvely applying techniques designed for sanitizing hard drives on SSDs, such as overwriting and using built-in secure erase commands is unreliable and sometimes results in all the data remaining intact," they said. "Furthermore, our results also show that sanitizing single files on an SSD is much more difficult than on a traditional hard drive."

How can SSDs be effectively secured or disposed of, short of physically destroying them? The researchers propose encrypting all data from the start, then destroying the encryption keys and overwriting every page of data to securely wipe the SSD and block future key recovery.

Implementing such an approach requires planning. "To properly secure data and take advantage of the performance benefits that SSDs offer, you should always encrypt the entire disk and do so as soon as the operating system is installed," said Chester Wisniewski, a senior security advisor for Sophos Canada, in a blog post. Based on the researchers' findings, "securely erasing SSDs after they have been used unencrypted is very difficult, and may be impossible in some cases," he said.

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Flash Poll
Current Issue
Cartoon
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2014-2627
Published: 2014-08-01
Unspecified vulnerability in HP NonStop NetBatch G06.14 through G06.32.01, H06 through H06.28, and J06 through J06.17.01 allows remote authenticated users to gain privileges for NetBatch job execution via unknown vectors.

CVE-2014-3009
Published: 2014-08-01
The GDS component in IBM InfoSphere Master Data Management - Collaborative Edition 10.0 through 11.0 and InfoSphere Master Data Management Server for Product Information Management 9.0 and 9.1 does not properly handle FRAME elements, which makes it easier for remote authenticated users to conduct ph...

CVE-2014-3302
Published: 2014-08-01
user.php in Cisco WebEx Meetings Server 1.5(.1.131) and earlier does not properly implement the token timer for authenticated encryption, which allows remote attackers to obtain sensitive information via a crafted URL, aka Bug ID CSCuj81708.

CVE-2012-6651
Published: 2014-07-31
Multiple directory traversal vulnerabilities in the Vitamin plugin before 1.1.0 for WordPress allow remote attackers to access arbitrary files via a .. (dot dot) in the path parameter to (1) add_headers.php or (2) minify.php.

CVE-2014-2970
Published: 2014-07-31
** REJECT ** DO NOT USE THIS CANDIDATE NUMBER. ConsultIDs: CVE-2014-5139. Reason: This candidate is a duplicate of CVE-2014-5139, and has also been used to refer to an unrelated topic that is currently outside the scope of CVE. This unrelated topic is a LibreSSL code change adding functionality ...

Best of the Web
Dark Reading Radio