CVE-2017-3169 - NULL Pointer Dereference

Severity

75%

Complexity

99%

Confidentiality

106%

In Apache httpd 2.2.x before 2.2.33 and 2.4.x before 2.4.26, mod_ssl may dereference a NULL pointer when third-party modules call ap_hook_process_connection() during an HTTP request to an HTTPS port.

In Apache httpd 2.2.x before 2.2.33 and 2.4.x before 2.4.26, mod_ssl may dereference a NULL pointer when third-party modules call ap_hook_process_connection() during an HTTP request to an HTTPS port.

CVSS 3.0 Base Score 9.8. CVSS Attack Vector: network. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

CVSS 2.0 Base Score 7.5. CVSS Attack Vector: network. CVSS Attack Complexity: low. CVSS Vector: (AV:N/AC:L/Au:N/C:P/I:P/A:P).

Demo Examples

NULL Pointer Dereference

CWE-476

While there are no complete fixes aside from conscientious programming, the following steps will go a long way to ensure that NULL pointer dereferences do not occur.


               
}
/* make use of pointer1 *//* ... */

If you are working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the if statement; and unlock when it has finished.

NULL Pointer Dereference

CWE-476

This example takes an IP address from a user, verifies that it is well formed and then looks up the hostname and copies it into a buffer.


               
}
strcpy(hostname, hp->h_name);/*routine that ensures user_supplied_addr is in the right format for conversion */

If an attacker provides an address that appears to be well-formed, but the address does not resolve to a hostname, then the call to gethostbyaddr() will return NULL. Since the code does not check the return value from gethostbyaddr (CWE-252), a NULL pointer dereference would then occur in the call to strcpy().

Note that this example is also vulnerable to a buffer overflow (see CWE-119).

NULL Pointer Dereference

CWE-476

In the following code, the programmer assumes that the system always has a property named "cmd" defined. If an attacker can control the program's environment so that "cmd" is not defined, the program throws a NULL pointer exception when it attempts to call the trim() method.


               
cmd = cmd.trim();

NULL Pointer Dereference

CWE-476

This application has registered to handle a URL when sent an intent:


               
}......
}
}
int length = URL.length();
...

The application assumes the URL will always be included in the intent. When the URL is not present, the call to getStringExtra() will return null, thus causing a null pointer exception when length() is called.

Overview

Type

Apache

First reported 7 years ago

2017-06-20 01:29:00

Last updated 4 years ago

2020-04-01 15:15:00

Affected Software

Apache Software Foundation Apache HTTP Server 2.2.0

2.2.0

Apache Software Foundation Apache HTTP Server 2.2.2

2.2.2

Apache Software Foundation Apache HTTP Server 2.2.3

2.2.3

Apache Software Foundation Apache HTTP Server 2.2.11

2.2.11

Apache Software Foundation Apache HTTP Server 2.2.12

2.2.12

Apache Software Foundation Apache HTTP Server 2.2.13

2.2.13

Apache Software Foundation Apache HTTP Server 2.2.14

2.2.14

Apache Software Foundation Apache HTTP Server 2.2.15

2.2.15

Apache Software Foundation Apache HTTP Server 2.2.16

2.2.16

Apache Software Foundation Apache HTTP Server 2.2.17

2.2.17

Apache Software Foundation Apache HTTP Server 2.2.18

2.2.18

Apache Software Foundation Apache HTTP Server 2.2.19

2.2.19

Apache Software Foundation Apache HTTP Server 2.2.20

2.2.20

Apache HTTP Server 2.2.21

2.2.21

Apache Software Foundation Apache HTTP Server 2.2.22

2.2.22

Apache Software Foundation Apache HTTP Server 2.2.23

2.2.23

Apache Software Foundation Apache HTTP Server 2.2.24

2.2.24

Apache Software Foundation Apache HTTP Server 2.2.25

2.2.25

Apache Software Foundation Apache HTTP Server 2.2.26

2.2.26

Apache Software Foundation Apache HTTP Server 2.2.27

2.2.27

Apache Software Foundation Apache HTTP Server 2.2.29

2.2.29

Apache Software Foundation Apache HTTP Server 2.2.31

2.2.31

Apache Software Foundation Apache HTTP Server 2.2.32

2.2.32

Apache Software Foundation Apache HTTP Server 2.4.1

2.4.1

Apache Software Foundation Apache HTTP Server 2.4.2

2.4.2

Apache Software Foundation Apache HTTP Server 2.4.10

2.4.10

Apache Software Foundation Apache HTTP Server 2.4.12

2.4.12

Apache Software Foundation Apache HTTP Server 2.4.16

2.4.16

Apache Software Foundation Apache HTTP Server 2.4.17

2.4.17

Apache Software Foundation Apache HTTP Server 2.4.18

2.4.18

Apache Software Foundation HTTP Server 2.4.20

2.4.20

Apache Software Foundation HTTP Server 2.4.23

2.4.23

Apache Software Foundation Apache HTTP Server 2.4.25

2.4.25

References

DSA-3896

http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html

99134

Third Party Advisory, VDB Entry

1038711

Third Party Advisory, VDB Entry

RHSA-2017:2478

RHSA-2017:2479

RHSA-2017:2483

RHSA-2017:3193

RHSA-2017:3194

RHSA-2017:3195

RHSA-2017:3475

RHSA-2017:3476

RHSA-2017:3477

https://github.com/gottburgm/Exploits/tree/master/CVE-2017-3169

[httpd-cvs] 20190815 svn commit: r1048743 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

[httpd-cvs] 20190815 svn commit: r1048742 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

[dev] 20170619 CVE-2017-3169: mod_ssl null pointer dereference

Patch, Vendor Advisory

[httpd-cvs] 20190815 svn commit: r1048743 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

[httpd-cvs] 20190815 svn commit: r1048742 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

[httpd-cvs] 20200401 svn commit: r1058586 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

[httpd-cvs] 20200401 svn commit: r1058586 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

[httpd-cvs] 20200401 svn commit: r1058587 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

[httpd-cvs] 20200401 svn commit: r1058587 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html

GLSA-201710-32

https://security.netapp.com/advisory/ntap-20180601-0002/

https://support.apple.com/HT208221

https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03908en_us

https://www.nomachine.com/SU08O00185

Mitigation, Third Party Advisory

https://www.tenable.com/security/tns-2019-09

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