Skip to main content

Resource Management Errors

CVE-2016-6581

Severity High
Score 7.5/10

Summary

A HTTP/2 implementation built using any version of the Python HPACK library between v1.0.0 and v2.2.0 could be targeted for a denial of service attack, specifically a so-called "HPACK Bomb" attack. This attack occurs when an attacker inserts a header field that is exactly the size of the HPACK dynamic header table into the dynamic header table. The attacker can then send a header block that is simply repeated requests to expand that field in the dynamic table. This can lead to a gigantic compression ratio of 4,096 or better, meaning that 16kB of data can decompress to 64MB of data on the target machine.

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

CWE-399 - Resource Management Errors

Resource management errors is not a weakness in and of itself, rather it is a category of weaknesses related to improper management of system resources. If not addressed, the weaknesses in this category can lead to unexpected software behavior, loss of access, file modification, sensitive information disclosure, system crash, denial of service, and code execution.

Advisory Timeline

  • Published