CVE-2016-6581

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.

CVSS v3 7.5 HIGH
CVSS v2.0 7.8 HIGH

7.5^/10

CVSS v3 : HIGH

Vector : AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

7.8^/10

CVSS v2.0 : HIGH

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

Exploitability : 10.0 / Impact : 6.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact COMPLETE

References

Link	Resource
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

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2017-01-10 15:59

Updated : 2023-12-10 12:01

NVD link : CVE-2016-6581

Mitre link : CVE-2016-6581

CVE.ORG link : CVE-2016-6581

JSON object : View

Products Affected

python

hpack
hyper

CWE

CWE-399

Resource Management Errors

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