CWE

Common Weakness Enumeration

A Community-Developed List of Software Weakness Types

CWE/SANS Top 25 Most Dangerous Software Errors
Home > CWE List > CWE- Individual Dictionary Definition (2.11)  
ID

CWE-55: Path Equivalence: '/./' (Single Dot Directory)

Weakness ID: 55
Abstraction: Variant
Status: Incomplete
Presentation Filter:
+ Description

Description Summary

A software system that accepts path input in the form of single dot directory exploit ('/./') without appropriate validation can lead to ambiguous path resolution and allow an attacker to traverse the file system to unintended locations or access arbitrary files.
+ Time of Introduction
  • Implementation
+ Applicable Platforms

Languages

All

+ Common Consequences
ScopeEffect
Confidentiality
Integrity

Technical Impact: Read files or directories; Modify files or directories

+ Observed Examples
ReferenceDescription
Server allows remote attackers to read source code for executable files by inserting a . (dot) into the URL.
Server allows remote attackers to read password-protected files via a /./ in the HTTP request.
Input Validation error
Possibly (could be a cleansing error)
"/./////etc" cleansed to ".///etc" then "/etc"
Server allows remote attackers to view password protected files via /./ in the URL.
+ Potential Mitigations

Phase: Implementation

Strategy: Input Validation

Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass whitelist validation schemes by introducing dangerous inputs after they have been checked.

+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness BaseWeakness Base41Improper Resolution of Path Equivalence
Development Concepts (primary)699
Research Concepts (primary)1000
ChildOfCategoryCategory981SFP Secondary Cluster: Path Traversal
Software Fault Pattern (SFP) Clusters (primary)888
+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
PLOVER/./ (single dot directory)
Software Fault PatternsSFP16Path Traversal
+ Content History
Submissions
Submission DateSubmitterOrganizationSource
PLOVERExternally Mined
Modifications
Modification DateModifierOrganizationSource
2008-07-01Eric DalciCigitalExternal
updated Time_of_Introduction
2008-09-08CWE Content TeamMITREInternal
updated Relationships, Taxonomy_Mappings
2011-06-01CWE Content TeamMITREInternal
updated Common_Consequences
2012-05-11CWE Content TeamMITREInternal
updated Observed_Examples, Relationships
2012-10-30CWE Content TeamMITREInternal
updated Potential_Mitigations
2014-07-30CWE Content TeamMITREInternal
updated Relationships, Taxonomy_Mappings
Previous Entry Names
Change DatePrevious Entry Name
2008-04-11Path Issue - Single Dot Directory - /./

More information is available — Please select a different filter.
Page Last Updated: May 05, 2017