CVE-2016-6581 - A HTTP/2 implementation built using any version of the Python HPACK library between v1.0.0 and v2.2.

CVE-2016-6581

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.

References

Vulnerable Configurations

cpe:2.3:a:python:hpack:1.0:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:1.0:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.0:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.0:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.0.1:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.0.1:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.1.1:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.1.1:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.2:*:*:*:*:*:*:*
cpe:2.3:a:python:hpack:2.2:*:*:*:*:*:*:*
cpe:2.3:a:python:hyper:0.4:*:*:*:*:*:*:*
cpe:2.3:a:python:hyper:0.4:*:*:*:*:*:*:*
cpe:2.3:a:python:hyper:0.6:*:*:*:*:*:*:*
cpe:2.3:a:python:hyper:0.6:*:*:*:*:*:*:*

CVSS

Base:	7.8 (as of 27-01-2017 - 19:41)
Impact:
Exploitability:

CWE

CWE-399

CAPEC

Access

Vector	Complexity	Authentication
NETWORK	LOW	NONE

Impact

Confidentiality	Integrity	Availability
NONE	NONE	COMPLETE

cvss-vector via4

AV:N/AC:L/Au:N/C:N/I:N/A:C

refmap via4

bid	92315
confirm	https://python-hyper.org/hpack/en/latest/security/CVE-2016-6581.html

Last major update

27-01-2017 - 19:41

Published

10-01-2017 - 15:59

Last modified

27-01-2017 - 19:41