137
Relevant to the view "Architectural Concepts" (CWE-1008)
Nature Type ID Name Page
MemberOf 1019 Validate Inputs 2433
Relevant to the view "Software Development" (CWE-699)
Nature Type ID Name Page
MemberOf 137 Data Neutralization Issues 2311
Weakness Ordinalities
Resultant :
Applicable Platforms
Language : Not Language-Specific (Prevalence = Undetermined)
Technology : Web Based (Prevalence = Often)
CWE Version 4.14
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-79: Improper Neutralization of Input During
Web Page Generation ('Cross-site Scripting') 166
Background Details
The Same Origin Policy states that browsers should limit the resources accessible to scripts
running on a given web site, or "origin", to the resources associated with that web site on the clientside,
and not the client-side resources of any other sites or "origins". The goal is to prevent one
site from being able to modify or read the contents of an unrelated site. Since the World Wide Web
involves interactions between many sites, this policy is important for browsers to enforce.
When referring to XSS, the Domain of a website is roughly equivalent to the resources associated
with that website on the client-side of the connection. That is, the domain can be thought of as all
resources the browser is storing for the user's interactions with this particular site.
Alternate Terms
XSS : A common abbreviation for Cross-Site Scripting.
HTML Injection : Used as a synonym of stored (Type 2) XSS.
CSS : In the early years after initial discovery of XSS, "CSS" was a commonly-used acronym.
However, this would cause confusion with "Cascading Style Sheets," so usage of this acronym has
declined significantly.
Likelihood Of Exploit
High
Common Consequences
Scope Impact Likelihood
Access Control
Confidentiality
Bypass Protection Mechanism
Read Application Data
The most common attack performed with cross-site
scripting involves the disclosure of information stored in
user cookies. Typically, a malicious user will craft a clientside
script, which -- when parsed by a web browser --
performs some activity (such as sending all site cookies to
a given E-mail address). This script will be loaded and run
by each user visiting the web site. Since the site requesting
to run the script has access to the cookies in question, the
malicious script does also.
Integrity
Confidentiality
Availability
Execute Unauthorized Code or Commands
In some circumstances it may be possible to run arbitrary
code on a victim's computer when cross-site scripting is
combined with other flaws.
Confidentiality
Integrity
Availability
Access Control
Execute Unauthorized Code or Commands
Bypass Protection Mechanism
Read Application Data
The consequence of an XSS attack is the same regardless
of whether it is stored or reflected. The difference is in how
the payload arrives at the server. XSS can cause a variety
of problems for the end user that range in severity from an
annoyance to complete account compromise. Some crosssite
scripting vulnerabilities can be exploited to manipulate
or steal cookies, create requests that can be mistaken for
those of a valid user, compromise confidential information,
or execute malicious code on the end user systems for
a variety of nefarious purposes. Other damaging attacks
include the disclosure of end user files, installation of
CWE Version 4.14
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-79: Improper Neutralization of Input During
Web Page Generation ('Cross-site Scripting')