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Loop with Unreachable Exit Condition ('Infinite Loop')

CVE-2021-40111

Severity Medium
Score 6.5/10

Summary

In Apache James, while fuzzing with Jazzer the IMAP parsing stack, we discover that crafted APPEND and STATUS IMAP command could be used to trigger infinite loops resulting in expensive CPU computations and OutOfMemory exceptions. This can be used for a Denial Of Service attack. The IMAP user needs to be authenticated to exploit this vulnerability. This affected Apache James prior to version 3.6.1. This vulnerability had been patched in Apache James 3.6.1 and higher. We recommend the upgrade.

  • LOW
  • NETWORK
  • NONE
  • UNCHANGED
  • NONE
  • LOW
  • NONE
  • HIGH

CWE-835 - Loop with Unreachable Exit Condition

Loops with multiple exits and flags detract from the quality of an application. They tend to make control structures difficult to understand, and introduce the risk of non-termination and other structural problems. The vulnerability “loop with unreachable exit condition” enables attackers to exploit this flaw, leading to denial of service.

Advisory Timeline

  • Published