RHSA-2021:1811 - Security Advisory

标题

An update for libvncserver is now available for Red Hat Enterprise Linux 8.

Red Hat Product Security has rated this update as having a security impact of Moderate. 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.

描述

LibVNCServer is a C library that enables you to implement VNC server functionality into own programs.

Security Fix(es):

• libvncserver: uninitialized memory contents are vulnerable to Information Leak (CVE-2018-21247)
• libvncserver: buffer overflow in ConnectClientToUnixSock() (CVE-2019-20839)
• libvncserver: libvncserver/rfbregion.c has a NULL pointer dereference (CVE-2020-14397)
• libvncserver: libvncclient/rfbproto.c does not limit TextChat size (CVE-2020-14405)
• libvncserver: libvncserver/rfbserver.c has a divide by zero which could result in DoS (CVE-2020-25708)

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.

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.4 Release Notes linked from the References section.

解决方案

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

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

受影响的产品

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.8 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.4 x86_64
• Red Hat Enterprise Linux Server - AUS 8.6 x86_64
• Red Hat Enterprise Linux Server - AUS 8.4 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.8 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.4 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.8 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.6 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.4 ppc64le
• Red Hat Enterprise Linux Server - TUS 8.8 x86_64
• Red Hat Enterprise Linux Server - TUS 8.6 x86_64
• Red Hat Enterprise Linux Server - TUS 8.4 x86_64
• Red Hat Enterprise Linux for ARM 64 8 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.8 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.6 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.4 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.8 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.6 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.4 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.8 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.4 x86_64
• Red Hat CodeReady Linux Builder for x86_64 8 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian 8 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 8 aarch64
• Red Hat CodeReady Linux Builder for IBM z Systems 8 s390x
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.8 x86_64
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.6 x86_64
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.4 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 8.8 ppc64le
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 8.6 ppc64le
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 8.4 ppc64le
• Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 8.8 s390x
• Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 8.6 s390x
• Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 8.4 s390x
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.8 aarch64
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.6 aarch64
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.4 aarch64

修复

• BZ - 1849877 - CVE-2019-20839 libvncserver: buffer overflow in ConnectClientToUnixSock()
• BZ - 1849886 - CVE-2018-21247 libvncserver: uninitialized memory contents are vulnerable to Information Leak
• BZ - 1860325 - CVE-2020-14405 libvncserver: libvncclient/rfbproto.c does not limit TextChat size
• BZ - 1860344 - CVE-2020-14397 libvncserver: libvncserver/rfbregion.c has a NULL pointer dereference
• BZ - 1896739 - CVE-2020-25708 libvncserver: libvncserver/rfbserver.c has a divide by zero which could result in DoS

CVE

• CVE-2018-21247
• CVE-2019-20839
• CVE-2020-14397
• CVE-2020-14405
• CVE-2020-25708

参考

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.4_release_notes/