var-201908-0421

Vulnerability from variot

Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service. The attacker requests a large amount of data from a specified resource over multiple streams. They manipulate window size and stream priority to force the server to queue the data in 1-byte chunks. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both. Multiple HTTP/2 implementations are vulnerable to a variety of denial-of-service (DoS) attacks. HTTP/2 is the second version of the hypertext transfer protocol, which is mainly used to ensure the communication between the client and the server. A resource management error vulnerability exists in HTTP/2. -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256

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Red Hat Security Advisory

Synopsis: Important: rh-nginx114-nginx security update Advisory ID: RHSA-2019:2775-01 Product: Red Hat Software Collections Advisory URL: https://access.redhat.com/errata/RHSA-2019:2775 Issue date: 2019-09-16 CVE Names: CVE-2019-9511 CVE-2019-9513 CVE-2019-9516 ==================================================================== 1. Summary:

An update for rh-nginx114-nginx is now available for Red Hat Software Collections.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Relevant releases/architectures:

Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) - aarch64, ppc64le, s390x, x86_64 Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4) - ppc64le, s390x, x86_64 Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5) - ppc64le, s390x, x86_64 Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) - ppc64le, s390x, x86_64 Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.7) - ppc64le, s390x, x86_64 Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) - x86_64

Description:

nginx is a web and proxy server supporting HTTP and other protocols, with a focus on high concurrency, performance, and low memory usage.

Security Fix(es):

HTTP/2: large amount of data request leads to denial of service (CVE-2019-9511)
HTTP/2: flood using PRIORITY frames resulting in excessive resource consumption (CVE-2019-9513)
HTTP/2: 0-length headers leads to denial of service (CVE-2019-9516)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution:

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The rh-nginx114-nginx service must be restarted for this update to take effect.

Bugs fixed (https://bugzilla.redhat.com/):

1735741 - CVE-2019-9513 HTTP/2: flood using PRIORITY frames resulting in excessive resource consumption 1741860 - CVE-2019-9511 HTTP/2: large amount of data requests leads to denial of service 1741864 - CVE-2019-9516 HTTP/2: 0-length headers lead to denial of service

Package List:

Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7):