Should the U.S. stockpile zero days?

Zero-day vulnerabilities live on average for 6.9 years and have a low rate of discovery by other entities, which could argue in favor of stockpiling them, according to a comprehensive study by the RAND Corporation.

broken lock
 

To hoard or not to hoard? That is the question that a RAND Corporation study explores in a new report, "Zero Days, Thousands of Nights: The Life and Times of Zero-Day Vulnerabilities and Their Exploits."

In the last year, disclosures by WikiLeaks and the hacker group The Shadow Brokers have focused attention on the stockpiling of zero-day exploits by U.S. intelligence agencies, which has raised a number of questions about U.S. policies on collecting and disclosing (or not disclosing) such vulnerabilities.

The concern hinges on whether the National Security Agency and CIA in particular are putting Americans at risk by not disclosing vulnerabilities that the agencies want to use for gathering intelligence.

An unnamed vulnerability research group gave RAND access to more than 200 zero-day exploits and their respective vulnerabilities over a 14-year period. RAND evaluated these in an attempt to develop metrics to determine when a vulnerability should be retained or disclosed.

RAND found that zero-days last on average for 6.9 years, with 25 percent lasting less than 1.5 years and 25 percent living more 9.5 years. They determined that "for a given stockpile of zero-day vulnerabilities, after a year, approximately 5.7 percent have been publicly discovered and disclosed by another entity."

According to RAND, there are no identifiable characteristics of a vulnerability that indicate whether it will have a long or short life. Once a vulnerability is discovered, the median time to develop an exploit is 22 days.

Although there is no "cut-and-dried" answer to the question of whether to stockpile vulnerabilities, RAND said there are two factors central to the debate. They are the longevity of a vulnerability, or "how long the vendor or public remains ignorant of the vulnerability," and the collision rate, or "the likelihood that a zero-day found by one entity will also be found independently by another."

Perhaps the hardest question to answer is how much overlap there is between zero-day stockpiles held by adversaries.

"If both sides have the same stockpiles, then some argue that there is little point to keeping them private -- whereas a smaller overlap might justify retention," RAND said.

Stakeholders also consider the cost of finding vulnerabilities and developing exploits, RAND said, as well as how long target systems go before being patched or updated as factors in determining whether to hold zero-days.

"At the most basic level, any serious attacker can always get an affordable zero-day for almost any target," said RAND. "The majority of the cost of a zero-day exploit does not come from labor, but rather the value inherent in them and the lack of supply."

RAND also said it is extremely difficult to quantify the value of using a zero-day, especially when there are often easier methods of penetration available given the lack of cyber hygiene in many organizations.

"Little is known about the true extent, use, benefit, and harm of zero-day exploits," RAND said. "Discussions are often speculative or based on what is discovered after the vulnerability has been exploited and detected in an attack."

Ultimately, the RAND report said the decision to stockpile zero-days is a case-by-case determination.

"Our analysis shows that zero-day vulnerabilities may have long average lifetimes and low collision rates," RAND said. "The small overlap may indicate that vulnerabilities are dense … or very hard to find… If zero-day vulnerabilities are very hard to find, then the small probability that others will find the same vulnerability may also support the argument to retain a stockpile."

RAND points out that the collision rates for zero-day vulnerabilities are nonzero, which means there is a possibility that an adversary may discover the same vulnerability.

"Then the potentially severe consequences of keeping the zero-day private and leaving a population vulnerable warrant immediate vulnerability disclosure and patch," according to the report. "In this line of thought, the best decision may be to stockpile only if one is confident that no one else will find the zero-day; disclose otherwise," RAND concluded.

X
This website uses cookies to enhance user experience and to analyze performance and traffic on our website. We also share information about your use of our site with our social media, advertising and analytics partners. Learn More / Do Not Sell My Personal Information
Accept Cookies
X
Cookie Preferences Cookie List

Do Not Sell My Personal Information

When you visit our website, we store cookies on your browser to collect information. The information collected might relate to you, your preferences or your device, and is mostly used to make the site work as you expect it to and to provide a more personalized web experience. However, you can choose not to allow certain types of cookies, which may impact your experience of the site and the services we are able to offer. Click on the different category headings to find out more and change our default settings according to your preference. You cannot opt-out of our First Party Strictly Necessary Cookies as they are deployed in order to ensure the proper functioning of our website (such as prompting the cookie banner and remembering your settings, to log into your account, to redirect you when you log out, etc.). For more information about the First and Third Party Cookies used please follow this link.

Allow All Cookies

Manage Consent Preferences

Strictly Necessary Cookies - Always Active

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Sale of Personal Data, Targeting & Social Media Cookies

Under the California Consumer Privacy Act, you have the right to opt-out of the sale of your personal information to third parties. These cookies collect information for analytics and to personalize your experience with targeted ads. You may exercise your right to opt out of the sale of personal information by using this toggle switch. If you opt out we will not be able to offer you personalised ads and will not hand over your personal information to any third parties. Additionally, you may contact our legal department for further clarification about your rights as a California consumer by using this Exercise My Rights link

If you have enabled privacy controls on your browser (such as a plugin), we have to take that as a valid request to opt-out. Therefore we would not be able to track your activity through the web. This may affect our ability to personalize ads according to your preferences.

Targeting cookies may be set through our site by our advertising partners. They may be used by those companies to build a profile of your interests and show you relevant adverts on other sites. They do not store directly personal information, but are based on uniquely identifying your browser and internet device. If you do not allow these cookies, you will experience less targeted advertising.

Social media cookies are set by a range of social media services that we have added to the site to enable you to share our content with your friends and networks. They are capable of tracking your browser across other sites and building up a profile of your interests. This may impact the content and messages you see on other websites you visit. If you do not allow these cookies you may not be able to use or see these sharing tools.

If you want to opt out of all of our lead reports and lists, please submit a privacy request at our Do Not Sell page.

Save Settings
Cookie Preferences Cookie List

Cookie List

A cookie is a small piece of data (text file) that a website – when visited by a user – asks your browser to store on your device in order to remember information about you, such as your language preference or login information. Those cookies are set by us and called first-party cookies. We also use third-party cookies – which are cookies from a domain different than the domain of the website you are visiting – for our advertising and marketing efforts. More specifically, we use cookies and other tracking technologies for the following purposes:

Strictly Necessary Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Functional Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Performance Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Sale of Personal Data

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.

Social Media Cookies

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.

Targeting Cookies

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.