CVE-2016-6581 (GCVE-0-2016-6581)

Vulnerability from cvelistv5 – Published: 2017-01-10 15:00 – Updated: 2024-08-06 01:36
VLAI
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.
Severity
7.5 (High)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • n/a
Assigner
References
Date Public
2016-08-04 00:00
Show details on NVD website
To clipboard 

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}



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