CVE-2015-0293 - Improper Input Validation

Severity

50%

Complexity

99%

Confidentiality

48%

The SSLv2 implementation in OpenSSL before 0.9.8zf, 1.0.0 before 1.0.0r, 1.0.1 before 1.0.1m, and 1.0.2 before 1.0.2a allows remote attackers to cause a denial of service (s2_lib.c assertion failure and daemon exit) via a crafted CLIENT-MASTER-KEY message.

The SSLv2 implementation in OpenSSL before 0.9.8zf, 1.0.0 before 1.0.0r, 1.0.1 before 1.0.1m, and 1.0.2 before 1.0.2a allows remote attackers to cause a denial of service (s2_lib.c assertion failure and daemon exit) via a crafted CLIENT-MASTER-KEY message.

CVSS 2.0 Base Score 5. CVSS Attack Vector: network. CVSS Attack Complexity: low. CVSS Vector: (AV:N/AC:L/Au:N/C:N/I:N/A:P).

Demo Examples

Improper Input Validation

CWE-20

This example demonstrates a shopping interaction in which the user is free to specify the quantity of items to be purchased and a total is calculated.


               
...

The user has no control over the price variable, however the code does not prevent a negative value from being specified for quantity. If an attacker were to provide a negative value, then the user would have their account credited instead of debited.

Improper Input Validation

CWE-20

This example asks the user for a height and width of an m X n game board with a maximum dimension of 100 squares.


               
.../* board dimensions */
die("No integer passed: Die evil hacker!\n");
die("No integer passed: Die evil hacker!\n");
die("Value too large: Die evil hacker!\n");

While this code checks to make sure the user cannot specify large, positive integers and consume too much memory, it does not check for negative values supplied by the user. As a result, an attacker can perform a resource consumption (CWE-400) attack against this program by specifying two, large negative values that will not overflow, resulting in a very large memory allocation (CWE-789) and possibly a system crash. Alternatively, an attacker can provide very large negative values which will cause an integer overflow (CWE-190) and unexpected behavior will follow depending on how the values are treated in the remainder of the program.

Improper Input Validation

CWE-20

The following example shows a PHP application in which the programmer attempts to display a user's birthday and homepage.


               
echo "Birthday: $birthday<br>Homepage: <a href=$homepage>click here</a>"

The programmer intended for $birthday to be in a date format and $homepage to be a valid URL. However, since the values are derived from an HTTP request, if an attacker can trick a victim into clicking a crafted URL with <script> tags providing the values for birthday and / or homepage, then the script will run on the client's browser when the web server echoes the content. Notice that even if the programmer were to defend the $birthday variable by restricting input to integers and dashes, it would still be possible for an attacker to provide a string of the form:


               
2009-01-09--

If this data were used in a SQL statement, it would treat the remainder of the statement as a comment. The comment could disable other security-related logic in the statement. In this case, encoding combined with input validation would be a more useful protection mechanism.

Furthermore, an XSS (CWE-79) attack or SQL injection (CWE-89) are just a few of the potential consequences when input validation is not used. Depending on the context of the code, CRLF Injection (CWE-93), Argument Injection (CWE-88), or Command Injection (CWE-77) may also be possible.

Improper Input Validation

CWE-20

This function attempts to extract a pair of numbers from a user-supplied string.


               
}
die("Did not specify integer value. Die evil hacker!\n");
/* proceed assuming n and m are initialized correctly */

This code attempts to extract two integer values out of a formatted, user-supplied input. However, if an attacker were to provide an input of the form:


               
123:

then only the m variable will be initialized. Subsequent use of n may result in the use of an uninitialized variable (CWE-457).

Improper Input Validation

CWE-20

The following example takes a user-supplied value to allocate an array of objects and then operates on the array.


               
}
list[0] = new Widget();
die("Negative value supplied for list size, die evil hacker!");

This example attempts to build a list from a user-specified value, and even checks to ensure a non-negative value is supplied. If, however, a 0 value is provided, the code will build an array of size 0 and then try to store a new Widget in the first location, causing an exception to be thrown.

Improper Input Validation

CWE-20

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

OpenSSL

First reported 10 years ago

2015-03-19 22:59:00

Last updated 7 years ago

2018-01-18 18:18:00

Affected Software

OpenSSL Project OpenSSL

OpenSSL Project OpenSSL 1.0.0

1.0.0

OpenSSL Project OpenSSL 1.0.0a

1.0.0a

OpenSSL Project OpenSSL 1.0.0b

1.0.0b

OpenSSL Project OpenSSL 1.0.0c

1.0.0c

OpenSSL Project OpenSSL 1.0.0d

1.0.0d

OpenSSL Project OpenSSL 1.0.0e

1.0.0e

OpenSSL Project OpenSSL 1.0.0f

1.0.0f

OpenSSL Project OpenSSL 1.0.0g

1.0.0g

OpenSSL Project OpenSSL 1.0.0h

1.0.0h

OpenSSL Project OpenSSL 1.0.0i

1.0.0i

OpenSSL Project OpenSSL 1.0.0j

1.0.0j

OpenSSL Project OpenSSL 1.0.0k

1.0.0k

OpenSSL Project OpenSSL 1.0.0l

1.0.0l

OpenSSL Project OpenSSL 1.0.0m

1.0.0m

OpenSSL Project OpenSSL 1.0.0n

1.0.0n

OpenSSL OpenSSL 1.0.0o

1.0.0o

OpenSSL Project OpenSSL 1.0.0p

1.0.0p

OpenSSL Project OpenSSL 1.0.0q

1.0.0q

OpenSSL Project OpenSSL 1.0.1

1.0.1

OpenSSL Project OpenSSL 1.0.1a

1.0.1a

OpenSSL Project OpenSSL 1.0.1b

1.0.1b

OpenSSL Project OpenSSL 1.0.1c

1.0.1c

OpenSSL Project OpenSSL 1.0.1d

1.0.1d

OpenSSL Project OpenSSL 1.0.1e

1.0.1e

OpenSSL Project OpenSSL 1.0.1f

1.0.1f

OpenSSL Project OpenSSL 1.0.1g

1.0.1g

OpenSSL Project OpenSSL 1.0.1h

1.0.1h

OpenSSL Project OpenSSL 1.0.1i

1.0.1i

OpenSSL Project OpenSSL 1.0.1j

1.0.1j

OpenSSL Project OpenSSL 1.0.1k

1.0.1k

OpenSSL Project OpenSSL 1.0.1l

1.0.1l

OpenSSL Project OpenSSL 1.0.2

1.0.2

References

http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10680

APPLE-SA-2015-06-30-2

FEDORA-2015-4303

FEDORA-2015-4320

FEDORA-2015-4300

FEDORA-2015-6951

FEDORA-2015-6855

SUSE-SU-2015:0541

SUSE-SU-2015:0578

SUSE-SU-2016:0617

SUSE-SU-2016:0620

SUSE-SU-2016:0621

SUSE-SU-2016:0624

openSUSE-SU-2016:0628

SUSE-SU-2016:0631

openSUSE-SU-2016:0637

openSUSE-SU-2016:0638

openSUSE-SU-2016:0640

SUSE-SU-2016:0641

openSUSE-SU-2016:0720

SUSE-SU-2016:1057

openSUSE-SU-2015:0554

SSRT102000

HPSBMU03380

HPSBMU03409

HPSBMU03397

RHSA-2015:0715

RHSA-2015:0716

RHSA-2015:0752

RHSA-2015:0800

http://support.apple.com/kb/HT204942

MDVSA-2015:062

MDVSA-2015:063

http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html

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

http://www.oracle.com/technetwork/topics/security/bulletinapr2015-2511959.html

http://www.oracle.com/technetwork/topics/security/bulletinjan2015-2370101.html

http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html

http://www.oracle.com/technetwork/topics/security/cpujul2015-2367936.html

http://www.oracle.com/technetwork/topics/security/cpuoct2015-2367953.html

http://www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html

73232

1031929

USN-2537-1

https://access.redhat.com/articles/1384453

https://bto.bluecoat.com/security-advisory/sa92

https://bugzilla.redhat.com/show_bug.cgi?id=1202404

https://git.openssl.org/?p=openssl.git;a=commit;h=86f8fb0e344d62454f8daf3e15236b2b59210756

https://kc.mcafee.com/corporate/index?page=content&id=SB10110

GLSA-201503-11

https://support.citrix.com/article/CTX216642

FreeBSD-SA-15:06

https://www.openssl.org/news/secadv_20150319.txt

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