Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| n/a / n/a | affected n/a |
CWE
No CWE identifiers supplied.
References
- http://www.securityfocus.com/bid/92315
- https://python-hyper.org/hpack/en/latest/security/CVE-2016-6581.html
ADP enrichment
No English description supplied.