Joe a company’s new security specialist is assigned a role to conduct monthly vulnerability scans across the
network. He notices that the scanner is returning a large amount of false positives or failed audits. Which of the
following should Joe recommend to remediate these issues?
A.
Ensure the vulnerability scanner is located in a segmented VLAN that has access to the company’s servers
B.
Ensure the vulnerability scanner is configured to authenticate with a privileged account
C.
Ensure the vulnerability scanner is attempting to exploit the weaknesses it discovers
D.
Ensure the vulnerability scanner is conducting antivirus scanning
Explanation:
The vulnerability scanner is returning false positives because it is trying to scan servers that it doesn’t have
access to; for example, servers on the Internet.
We need to ensure that the local network servers only are scanned. We can do this by locating the vulnerability
scanner in a segmented VLAN that has access to the company’s servers.
A false positive is an error in some evaluation process in which a condition tested for is mistakenly found to
have been detected.
In spam filters, for example, a false positive is a legitimate message mistakenly marked as UBE –unsolicited
bulk email, as junk email is more formally known. Messages that are determined to be spam — whethercorrectly or incorrectly — may be rejected by a server or client-side spam filter and returned to the sender as
bounce e-mail.
One problem with many spam filtering tools is that if they are configured stringently enough to be effective,
there is a fairly high chance of getting false positives. The risk of accidentally blocking an important message
has been enough to deter many companies from implementing any anti-spam measures at all.
False positives are also common in security systems. A host intrusion prevention system (HIPS), for example,
looks for anomalies, such as deviations in bandwidth, protocols and ports. When activity varies outside of an
acceptable range, for example, a remote application attempting to open a normally closed port — an intrusion
may be in progress. However, an anomaly, such as a sudden spike in bandwidth use, does not guarantee an
actual attack, so this approach amounts to an educated guess and the chance for false positives can be high.
False positives contrast with false negatives, which are results indicating mistakenly that some condition tested
for is absent.