Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write (many of) the bytes on the wire. The attacker then sends a stream of requests for a large response object. Depending on how the servers queue the responses, this can consume excess memory, CPU, or both.

References[email protected][email protected][email protected][email protected][email protected][email protected][email protected]/message/4ZQGHE3WTYLYAYJEIDJVF2FIGQTAYPMC/[email protected]/message/BP556LEG3WENHZI5TAQ6ZEBFTJB4E2IS/[email protected]/message/CMNFX5MNYRWWIMO4BTKYQCGUDMHO3AXP/[email protected]/message/XHTKU7YQ5EEP2XNSAV4M4VJ7QCBOJMOD/


Source: MITRE

Published: 2019-08-13

Updated: 2020-10-22

Type: CWE-770

Risk Information

CVSS v2.0

Base Score: 7.8

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

Impact Score: 6.9

Exploitability Score: 10

Severity: HIGH

CVSS v3.0

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Impact Score: 3.6

Exploitability Score: 3.9

Severity: HIGH