CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:N/I:N/A:C
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
Percentile
40.6%
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.
Vendor | Product | Version | CPE |
---|---|---|---|
python | hpack | 1.0 | cpe:2.3:a:python:hpack:1.0:*:*:*:*:*:*:* |
python | hpack | 2.0 | cpe:2.3:a:python:hpack:2.0:*:*:*:*:*:*:* |
python | hpack | 2.0.1 | cpe:2.3:a:python:hpack:2.0.1:*:*:*:*:*:*:* |
python | hpack | 2.1.1 | cpe:2.3:a:python:hpack:2.1.1:*:*:*:*:*:*:* |
python | hpack | 2.2 | cpe:2.3:a:python:hpack:2.2:*:*:*:*:*:*:* |
python | hyper | 0.4 | cpe:2.3:a:python:hyper:0.4:*:*:*:*:*:*:* |
python | hyper | 0.6 | cpe:2.3:a:python:hyper:0.6:*:*:*:*:*:*:* |
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:N/I:N/A:C
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
Percentile
40.6%