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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2016-6581 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 3.x Severity and Vector Strings:

NIST CVSS score
NIST: NVD
Base Score:  7.5 HIGH
Vector:  CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

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Hyperlink Resource
http://www.securityfocus.com/bid/92315 Third Party Advisory  VDB Entry 
http://www.securityfocus.com/bid/92315 Third Party Advisory  VDB Entry 
https://python-hyper.org/hpack/en/latest/security/CVE-2016-6581.html Mitigation  Vendor Advisory 
https://python-hyper.org/hpack/en/latest/security/CVE-2016-6581.html Mitigation  Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-399 Resource Management Errors cwe source acceptance level NIST  

Known Affected Software Configurations Switch to CPE 2.2

Configuration 1 ( hide )
 cpe:2.3:a:python:hpack:1.0:*:*:*:*:*:*:*
   Show Matching CPE(s)
 cpe:2.3:a:python:hpack:2.0:*:*:*:*:*:*:*
   Show Matching CPE(s)
 cpe:2.3:a:python:hpack:2.0.1:*:*:*:*:*:*:*
   Show Matching CPE(s)
 cpe:2.3:a:python:hpack:2.1.1:*:*:*:*:*:*:*
   Show Matching CPE(s)
 cpe:2.3:a:python:hpack:2.2:*:*:*:*:*:*:*
   Show Matching CPE(s)
 cpe:2.3:a:python:hyper:0.4:*:*:*:*:*:*:*
   Show Matching CPE(s)
 cpe:2.3:a:python:hyper:0.6:*:*:*:*:*:*:*
   Show Matching CPE(s)

Denotes Vulnerable Software
Are we missing a CPE here? Please let us know.

Change History

5 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2016-6581
NVD Published Date:
01/10/2017
NVD Last Modified:
11/20/2024
Source:
MITRE