Not Failing Securely ('Failing Open')
|ID: 636||Date: (C)2012-05-14 (M)2012-11-08|
|Type: weakness||Status: DRAFT|
|Abstraction Type: Class|
When the product encounters an error condition or failure, its
design requires it to fall back to a state that is less secure than other
options that are available, such as selecting the weakest encryption algorithm
or using the most permissive access control restrictions.
Extended DescriptionBy entering a less secure state, the product inherits the weaknesses
associated with that state, making it easier to compromise. At the least, it
causes administrators to have a false sense of security. This weakness
typically occurs as a result of wanting to "fail functional" to minimize
administration and support costs, instead of "failing safe."
Applicable PlatformsLanguage Class: All
Time Of Introduction
- Architecture and Design
|Access_Control ||Bypass protection
mechanism ||Intended access restrictions can be bypassed, which is often
contradictory to what the product's administrator expects. |
|Architecture and Design || ||Subdivide and allocate resources and components so that a failure in
one part does not affect the entire product. || || |
|CWE-636 ChildOf CWE-889 ||Category ||CWE-888 || |
Demonstrative Examples (Details)
- Switches may revert their functionality to that of hubs when the
table used to map ARP information to the switch interface overflows, such as
when under a spoofing attack. This results in traffic being broadcast to an
eavesdropper, instead of being sent only on the relevant switch interface.
To mitigate this type of problem, the developer could limit the number of
ARP entries that can be recorded for a given switch interface, while other
interfaces may keep functioning normally. Configuration options can be
provided on the appropriate actions to be taken in case of a detected
failure, but safe defaults should be used.
- CVE-2007-5277 : The failure of connection attempts in a web browser resets DNS pin restrictions. An attacker can then bypass the same origin policy by rebinding a domain name to a different IP address. This was an attempt to "fail functional."
- CVE-2006-4407 : Incorrect prioritization leads to the selection of a weaker cipher. Although it is not known whether this issue occurred in implementation or design, it is feasible that a poorly designed algorithm could be a factor.
For more examples, refer to CVE relations in the bottom box.
White Box Definitions None
Black Box Definitions None
|OWASP Top Ten 2004 ||A7 ||Improper Error Handling ||CWE_More_Specific |
- Jerome H. Saltzer Michael D. Schroeder .The Protection of Information in Computer
Systems. Proceedings of the IEEE 63. Published on September, 1975.
- Sean Barnum Michael Gegick .Failing Securely. Published on 2005-12-05.