Description
The product requires that an actor should only be able to perform an action once, or to have only one unique action, but the product does not enforce or improperly enforces this restriction.
In various applications, a user is only expected to perform a certain action once, such as voting, requesting a refund, or making a purchase. When this restriction is not enforced, sometimes this can have security implications. For example, in a voting application, an attacker could attempt to "stuff the ballot box" by voting multiple times. If these votes are counted separately, then the attacker could directly affect who wins the vote. This could have significant business impact depending on the purpose of the product.
Potential Impact
Other
Varies by Context
Real-World CVE Examples
| CVE ID | Description |
|---|---|
| CVE-2008-0294 | Ticket-booking web application allows a user to lock a seat more than once. |
| CVE-2005-4051 | CMS allows people to rate downloads by voting more than once. |
| CVE-2002-216 | Polling software allows people to vote more than once by setting a cookie. |
| CVE-2003-1433 | Chain: lack of validation of a challenge key in a game allows a player to register multiple times and lock other players out of the game. |
| CVE-2002-1018 | Library feature allows attackers to check out the same e-book multiple times, preventing other users from accessing copies of the e-book. |
| CVE-2009-2346 | Protocol implementation allows remote attackers to cause a denial of service (call-number exhaustion) by initiating many message exchanges. |
Related Weaknesses
Frequently Asked Questions
What is CWE-837?
CWE-837 (Improper Enforcement of a Single, Unique Action) is a software weakness identified by MITRE's Common Weakness Enumeration. It is classified as a Base-level weakness. The product requires that an actor should only be able to perform an action once, or to have only one unique action, but the product does not enforce or improperly enforces this restriction.
How can CWE-837 be exploited?
Attackers can exploit CWE-837 (Improper Enforcement of a Single, Unique Action) to varies by context. This weakness is typically introduced during the Implementation phase of software development.
How do I prevent CWE-837?
Follow secure coding practices, conduct code reviews, and use automated security testing tools (SAST/DAST) to detect this weakness early in the development lifecycle.
What is the severity of CWE-837?
CWE-837 is classified as a Base-level weakness (Medium abstraction). It has been observed in 6 real-world CVEs.