CVE-2016-4979

7.5 HIGH
Published: July 06, 2016 Modified: May 06, 2026
View on NVD

Description

The Apache HTTP Server 2.4.18 through 2.4.20, when mod_http2 and mod_ssl are enabled, does not properly recognize the "SSLVerifyClient require" directive for HTTP/2 request authorization, which allows remote attackers to bypass intended access restrictions by leveraging the ability to send multiple requests over a single connection and aborting a renegotiation.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://httpd.apache.org/security/vulnerabilities_24.html
Source: secalert@redhat.com
Patch Vendor Advisory
http://packetstormsecurity.com/files/137771/Apache-2.4.20-X509-Authentication-Bypass.html
Source: secalert@redhat.com
http://seclists.org/fulldisclosure/2016/Jul/11
Source: secalert@redhat.com
http://www.apache.org/dist/httpd/CHANGES_2.4
Source: secalert@redhat.com
http://www.openwall.com/lists/oss-security/2016/07/05/5
Source: secalert@redhat.com
http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
Source: secalert@redhat.com
http://www.oracle.com/technetwork/topics/security/bulletinoct2016-3090566.html
Source: secalert@redhat.com
http://www.securityfocus.com/bid/91566
Source: secalert@redhat.com
http://www.securitytracker.com/id/1036225
Source: secalert@redhat.com
https://access.redhat.com/errata/RHSA-2016:1420
Source: secalert@redhat.com
https://github.com/apache/httpd/commit/2d0e4eff04ea963128a41faaef21f987272e05a2
Source: secalert@redhat.com
https://lists.apache.org/thread.html/56c2e7cc9deb1c12a843d0dc251ea7fd3e7e80293cde02fcd65286ba%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/84a3714f0878781f6ed84473d1a503d2cc382277e100450209231830%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/r04e89e873d54116a0635ef2f7061c15acc5ed27ef7500997beb65d6f%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/r76142b8c5119df2178be7c2dba88fde552eedeec37ea993dfce68d1d%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/rb14daf9cc4e28d18cdc15d6a6ca74e565672fabf7ad89541071d008b%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa1a1ea464b93f0a%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df39b094be286b9e%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/rd18c3c43602e66f9cdcf09f1de233804975b9572b0456cc582390b6f%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/re1e3a24664d35bcd0a0e793e0b5fc6ca6c107f99a1b2c545c5d4b467%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/re3d27b6250aa8548b8845d314bb8a350b3df326cacbbfdfe4d455234%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9%40%3Ccvs.httpd.apache.org%3E
Source: secalert@redhat.com
https://security.gentoo.org/glsa/201610-02
Source: secalert@redhat.com
https://security.netapp.com/advisory/ntap-20180601-0001/
Source: secalert@redhat.com
http://httpd.apache.org/security/vulnerabilities_24.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Vendor Advisory
http://packetstormsecurity.com/files/137771/Apache-2.4.20-X509-Authentication-Bypass.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://seclists.org/fulldisclosure/2016/Jul/11
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.apache.org/dist/httpd/CHANGES_2.4
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2016/07/05/5
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.oracle.com/technetwork/topics/security/bulletinoct2016-3090566.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.securityfocus.com/bid/91566
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.securitytracker.com/id/1036225
Source: af854a3a-2127-422b-91ae-364da2661108
https://access.redhat.com/errata/RHSA-2016:1420
Source: af854a3a-2127-422b-91ae-364da2661108
https://github.com/apache/httpd/commit/2d0e4eff04ea963128a41faaef21f987272e05a2
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/56c2e7cc9deb1c12a843d0dc251ea7fd3e7e80293cde02fcd65286ba%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/84a3714f0878781f6ed84473d1a503d2cc382277e100450209231830%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/r04e89e873d54116a0635ef2f7061c15acc5ed27ef7500997beb65d6f%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/r76142b8c5119df2178be7c2dba88fde552eedeec37ea993dfce68d1d%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/rb14daf9cc4e28d18cdc15d6a6ca74e565672fabf7ad89541071d008b%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa1a1ea464b93f0a%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df39b094be286b9e%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/rd18c3c43602e66f9cdcf09f1de233804975b9572b0456cc582390b6f%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/re1e3a24664d35bcd0a0e793e0b5fc6ca6c107f99a1b2c545c5d4b467%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/re3d27b6250aa8548b8845d314bb8a350b3df326cacbbfdfe4d455234%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9%40%3Ccvs.httpd.apache.org%3E
Source: af854a3a-2127-422b-91ae-364da2661108
https://security.gentoo.org/glsa/201610-02
Source: af854a3a-2127-422b-91ae-364da2661108
https://security.netapp.com/advisory/ntap-20180601-0001/
Source: af854a3a-2127-422b-91ae-364da2661108

50 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
17.4%
95th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-284

Affected Vendors

apache

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