High severity · published Jul 6, 2016
CVE-2016-4979
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…
7.5
CVSS
18.8%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)18.8% · higher than 97% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HS
HTTP Server · Apache
2.4.18; 2.4.19; 2.4.20 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2016-4979
CVE.org
https://www.cve.org/CVERecord?id=CVE-2016-4979
Patch
http://httpd.apache.org/security/vulnerabilities_24.html
packetstormsecurity.com
http://packetstormsecurity.com/files/137771/Apache-2.4.20-X509-Authentication-Bypass.html
seclists.org
http://seclists.org/fulldisclosure/2016/Jul/11
www.apache.org
http://www.apache.org/dist/httpd/CHANGES_2.4
www.openwall.com
http://www.openwall.com/lists/oss-security/2016/07/05/5
www.oracle.com
http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
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