Rapid7

vulnerability

Debian: CVE-2019-9515: h2o, trafficserver -- security update

Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Aug 13, 2019
Added
Oct 23, 2019
Modified
Mar 30, 2026

Description

Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a denial of service. The attacker sends a stream of SETTINGS frames to the peer. Since the RFC requires that the peer reply with one acknowledgement per SETTINGS frame, an empty SETTINGS frame is almost equivalent in behavior to a ping. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both.

Solutions

debian-upgrade-h2odebian-upgrade-trafficserver
Title
Rapid7 Labs

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