7.5
HIGH
CVE-2016-4979
Apache HTTP Server mod_http2 mod_ssl SSL Client Certificate Bypass
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.

INFO

Published Date :

July 6, 2016, 2:59 p.m.

Last Modified :

Nov. 7, 2023, 2:32 a.m.

Remotely Exploitable :

Yes !

Impact Score :

3.6

Exploitability Score :

3.9
Public PoC/Exploit Available at Github

CVE-2016-4979 has a 6 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2016-4979 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Apache http_server
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2016-4979.

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

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

None

Python

Updated: 6 months ago
0 stars 0 fork 0 watcher
Born at : May 18, 2024, 2:30 p.m. This repo has been linked 57 different CVEs too.

None

Updated: 1 year, 4 months ago
0 stars 0 fork 0 watcher
Born at : June 30, 2023, 2:41 p.m. This repo has been linked 78 different CVEs too.

DC-3 is another purposely built vulnerable lab with the intent of gaining experience in the world of penetration testing. As with the previous DC releases, this one is designed with beginners in mind, although this time around, there is only one flag, one entry point and no clues at all.

Updated: 2 years, 6 months ago
2 stars 1 fork 1 watcher
Born at : June 16, 2021, 5:41 a.m. This repo has been linked 37 different CVEs too.

This is a boot2root VM and is a continuation of the Basic Pentesting series. This series is designed to help newcomers to penetration testing develop pentesting skills and have fun exploring part of the offensive side of security. VirtualBox is the recommended platform for this challenge (though it should also work with VMware -- however, I haven’t tested that). This VM is a moderate step up in difficulty from the first entry in this series. If you’ve solved the first entry and have tried a few other beginner-oriented challenges, this VM should be a good next step. Once again, this challenge contains multiple initial exploitation vectors and privilege escalation vulnerabilities. Your goal is to remotely attack the VM, gain root privileges, and read the flag located at /root/flag.txt. Once you’ve finished, try to find other vectors you might have missed! If you’d like to send me a link to your writeup, enjoyed the VM or have questions or feedback, feel free to contact me at: [email protected] If you finished the VM, please also consider posting a writeup! Writeups help you internalize what you worked on and help anyone else who might be struggling or wants to see someone else’s process. There were lots of wonderful writeups for Basic Pentesting: 1, and I look forward to reading the writeups for this challenge.

Updated: 1 year, 4 months ago
5 stars 5 fork 5 watcher
Born at : May 25, 2021, 9:07 a.m. This repo has been linked 78 different CVEs too.

None

Python

Updated: 7 months, 2 weeks ago
6 stars 3 fork 3 watcher
Born at : April 12, 2021, 4:06 a.m. This repo has been linked 57 different CVEs too.

Tools that utilize the Red Hat Security Data API

Python

Updated: 2 months, 3 weeks ago
60 stars 25 fork 25 watcher
Born at : Oct. 14, 2016, 4:41 p.m. This repo has been linked 57 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2016-4979 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2016-4979 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/56c2e7cc9deb1c12a843d0dc251ea7fd3e7e80293cde02fcd65286ba%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/84a3714f0878781f6ed84473d1a503d2cc382277e100450209231830%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/rd18c3c43602e66f9cdcf09f1de233804975b9572b0456cc582390b6f%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/re3d27b6250aa8548b8845d314bb8a350b3df326cacbbfdfe4d455234%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa1a1ea464b93f0a%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/re1e3a24664d35bcd0a0e793e0b5fc6ca6c107f99a1b2c545c5d4b467%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/r04e89e873d54116a0635ef2f7061c15acc5ed27ef7500997beb65d6f%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df39b094be286b9e%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/rb14daf9cc4e28d18cdc15d6a6ca74e565672fabf7ad89541071d008b%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Added Reference Red Hat, Inc. https://lists.apache.org/thread.html/r76142b8c5119df2178be7c2dba88fde552eedeec37ea993dfce68d1d%40%3Ccvs.httpd.apache.org%3E [No types assigned]
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/56c2e7cc9deb1c12a843d0dc251ea7fd3e7e80293cde02fcd65286ba@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/84a3714f0878781f6ed84473d1a503d2cc382277e100450209231830@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/rd18c3c43602e66f9cdcf09f1de233804975b9572b0456cc582390b6f@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/re3d27b6250aa8548b8845d314bb8a350b3df326cacbbfdfe4d455234@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/re1e3a24664d35bcd0a0e793e0b5fc6ca6c107f99a1b2c545c5d4b467@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa1a1ea464b93f0a@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/r04e89e873d54116a0635ef2f7061c15acc5ed27ef7500997beb65d6f@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df39b094be286b9e@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/rb14daf9cc4e28d18cdc15d6a6ca74e565672fabf7ad89541071d008b@%3Ccvs.httpd.apache.org%3E
    Removed Reference Red Hat, Inc. https://lists.apache.org/thread.html/r76142b8c5119df2178be7c2dba88fde552eedeec37ea993dfce68d1d@%3Ccvs.httpd.apache.org%3E
  • CVE Modified by [email protected]

    Jun. 06, 2021

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df39b094be286b9e@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/rb14daf9cc4e28d18cdc15d6a6ca74e565672fabf7ad89541071d008b@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/r76142b8c5119df2178be7c2dba88fde552eedeec37ea993dfce68d1d@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
  • CVE Modified by [email protected]

    Mar. 30, 2021

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/re1e3a24664d35bcd0a0e793e0b5fc6ca6c107f99a1b2c545c5d4b467@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa1a1ea464b93f0a@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/r04e89e873d54116a0635ef2f7061c15acc5ed27ef7500997beb65d6f@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
  • CVE Modified by [email protected]

    Apr. 01, 2020

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/re3d27b6250aa8548b8845d314bb8a350b3df326cacbbfdfe4d455234@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
  • CVE Modified by [email protected]

    Apr. 01, 2020

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/rd18c3c43602e66f9cdcf09f1de233804975b9572b0456cc582390b6f@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
  • CVE Modified by [email protected]

    Aug. 15, 2019

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/56c2e7cc9deb1c12a843d0dc251ea7fd3e7e80293cde02fcd65286ba@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/84a3714f0878781f6ed84473d1a503d2cc382277e100450209231830@%3Ccvs.httpd.apache.org%3E [No Types Assigned]
  • CVE Modified by [email protected]

    Jun. 03, 2018

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20180601-0001/ [No Types Assigned]
  • CVE Modified by [email protected]

    Jul. 01, 2017

    Action Type Old Value New Value
    Added Reference https://security.gentoo.org/glsa/201610-02 [No Types Assigned]
  • CVE Modified by [email protected]

    Nov. 28, 2016

    Action Type Old Value New Value
    Added Reference http://www.securityfocus.com/bid/91566 [No Types Assigned]
    Added Reference http://seclists.org/fulldisclosure/2016/Jul/11 [No Types Assigned]
    Added Reference http://packetstormsecurity.com/files/137771/Apache-2.4.20-X509-Authentication-Bypass.html [No Types Assigned]
    Added Reference https://access.redhat.com/errata/RHSA-2016:1420 [No Types Assigned]
    Added Reference http://www.securitytracker.com/id/1036225 [No Types Assigned]
  • CVE Modified by [email protected]

    Oct. 27, 2016

    Action Type Old Value New Value
    Added Reference http://www.oracle.com/technetwork/topics/security/bulletinoct2016-3090566.html
  • CVE Modified by [email protected]

    Oct. 26, 2016

    Action Type Old Value New Value
    Added Reference http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
  • Modified Analysis by [email protected]

    Jul. 08, 2016

    Action Type Old Value New Value
    Added CPE Configuration Configuration 1 OR *cpe:2.3:a:apache:http_server:2.4.20:*:*:*:*:*:*:* *cpe:2.3:a:apache:http_server:2.4.19:*:*:*:*:*:*:* *cpe:2.3:a:apache:http_server:2.4.18:*:*:*:*:*:*:*
    Added CVSS V2 (AV:N/AC:L/Au:N/C:N/I:P/A:N)
    Added CVSS V3 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
    Changed Reference Type http://httpd.apache.org/security/vulnerabilities_24.html No Types Assigned http://httpd.apache.org/security/vulnerabilities_24.html Advisory, Patch
    Added CWE CWE-284
  • Initial Analysis by [email protected]

    Jul. 07, 2016

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Jul. 07, 2016

    Action Type Old Value New Value
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2016-4979 is associated with the following CWEs:

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.21 }} 0.00%

score

0.57191

percentile

CVSS30 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability