RHSA-2017:3193 - Security Advisory

Topic

An update for httpd is now available for Red Hat Enterprise Linux 7.2 Extended Update Support.

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.

Description

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.

Security Fix(es):

• It was discovered that the httpd's mod_auth_digest module did not properly initialize memory before using it when processing certain headers related to digest authentication. A remote attacker could possibly use this flaw to disclose potentially sensitive information or cause httpd child process to crash by sending specially crafted requests to a server. (CVE-2017-9788)
• It was discovered that the use of httpd's ap_get_basic_auth_pw() API function outside of the authentication phase could lead to authentication bypass. A remote attacker could possibly use this flaw to bypass required authentication if the API was used incorrectly by one of the modules used by httpd. (CVE-2017-3167)
• A NULL pointer dereference flaw was found in the httpd's mod_ssl module. A remote attacker could use this flaw to cause an httpd child process to crash if another module used by httpd called a certain API function during the processing of an HTTPS request. (CVE-2017-3169)
• A buffer over-read flaw was found in the httpd's ap_find_token() function. A remote attacker could use this flaw to cause httpd child process to crash via a specially crafted HTTP request. (CVE-2017-7668)
• A buffer over-read flaw was found in the httpd's mod_mime module. A user permitted to modify httpd's MIME configuration could use this flaw to cause httpd child process to crash. (CVE-2017-7679)
• A use-after-free flaw was found in the way httpd handled invalid and previously unregistered HTTP methods specified in the Limit directive used in an .htaccess file. A remote attacker could possibly use this flaw to disclose portions of the server memory, or cause httpd child process to crash. (CVE-2017-9798)

Red Hat would like to thank Hanno Böck for reporting CVE-2017-9798.

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

After installing the updated packages, the httpd daemon will be restarted automatically.

Affected Products

• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.2 x86_64
• Red Hat Enterprise Linux Server - AUS 7.2 x86_64
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.2 s390x
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.2 ppc64
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.2 ppc64le
• Red Hat Enterprise Linux Server - TUS 7.2 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.2 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.2 x86_64

Fixes

• BZ - 1463194 - CVE-2017-3167 httpd: ap_get_basic_auth_pw() authentication bypass
• BZ - 1463197 - CVE-2017-3169 httpd: mod_ssl NULL pointer dereference
• BZ - 1463205 - CVE-2017-7668 httpd: ap_find_token() buffer overread
• BZ - 1463207 - CVE-2017-7679 httpd: mod_mime buffer overread
• BZ - 1470748 - CVE-2017-9788 httpd: Uninitialized memory reflection in mod_auth_digest
• BZ - 1490344 - CVE-2017-9798 httpd: Use-after-free by limiting unregistered HTTP method (Optionsbleed)

CVEs

• CVE-2017-3167
• CVE-2017-3169
• CVE-2017-7668
• CVE-2017-7679
• CVE-2017-9788
• CVE-2017-9798

References

• https://access.redhat.com/security/updates/classification/#important