Insufficient Session Expiration

Incomplete Base
Structure: Simple
Description

According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization."

Common Consequences 1
Scope: Access Control

Impact: Bypass Protection Mechanism

Detection Methods 1
Automated Static AnalysisHigh
Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
Potential Mitigations 1
Phase: Implementation
Set sessions/credentials expiration date.
Demonstrative Examples 1
The following snippet was taken from a J2EE web.xml deployment descriptor in which the session-timeout parameter is explicitly defined (the default value depends on the container). In this case the value is set to -1, which means that a session will never expire.

Code Example:

Bad
Java
java
Modes of Introduction
Architecture and Design
Implementation
Taxonomy Mapping
  • WASC
Notes
OtherThe lack of proper session expiration may improve the likely success of certain attacks. For example, an attacker may intercept a session ID, possibly via a network sniffer or Cross-site Scripting attack. Although short session expiration times do not help if a stolen token is immediately used, they will protect against ongoing replaying of the session ID. In another scenario, a user might access a web site from a shared computer (such as at a library, Internet cafe, or open work environment). Insufficient Session Expiration could allow an attacker to use the browser's back button to access web pages previously accessed by the victim.