ID CVE-2016-7444
Summary The gnutls_ocsp_resp_check_crt function in lib/x509/ocsp.c in GnuTLS before 3.4.15 and 3.5.x before 3.5.4 does not verify the serial length of an OCSP response, which might allow remote attackers to bypass an intended certificate validation mechanism via vectors involving trailing bytes left by gnutls_malloc.
References
Vulnerable Configurations
  • GNU GnuTLS 3.4.14
    cpe:2.3:a:gnu:gnutls:3.4.14
  • GNU GnuTLS 3.5.0
    cpe:2.3:a:gnu:gnutls:3.5.0
  • GNU GnuTLS 3.5.1
    cpe:2.3:a:gnu:gnutls:3.5.1
  • GNU GnuTLS 3.5.2
    cpe:2.3:a:gnu:gnutls:3.5.2
  • GNU GnuTLS 3.5.3
    cpe:2.3:a:gnu:gnutls:3.5.3
CVSS
Base: 5.0 (as of 27-09-2016 - 15:05)
Impact:
Exploitability:
CWE CWE-264
CAPEC
  • Accessing, Modifying or Executing Executable Files
    An attack of this type exploits a system's configuration that allows an attacker to either directly access an executable file, for example through shell access; or in a possible worst case allows an attacker to upload a file and then execute it. Web servers, ftp servers, and message oriented middleware systems which have many integration points are particularly vulnerable, because both the programmers and the administrators must be in synch regarding the interfaces and the correct privileges for each interface.
  • Leverage Executable Code in Non-Executable Files
    An attack of this type exploits a system's trust in configuration and resource files, when the executable loads the resource (such as an image file or configuration file) the attacker has modified the file to either execute malicious code directly or manipulate the target process (e.g. application server) to execute based on the malicious configuration parameters. Since systems are increasingly interrelated mashing up resources from local and remote sources the possibility of this attack occurring is high. The attack can be directed at a client system, such as causing buffer overrun through loading seemingly benign image files, as in Microsoft Security Bulletin MS04-028 where specially crafted JPEG files could cause a buffer overrun once loaded into the browser. Another example targets clients reading pdf files. In this case the attacker simply appends javascript to the end of a legitimate url for a pdf (http://www.gnucitizen.org/blog/danger-danger-danger/) http://path/to/pdf/file.pdf#whatever_name_you_want=javascript:your_code_here The client assumes that they are reading a pdf, but the attacker has modified the resource and loaded executable javascript into the client's browser process. The attack can also target server processes. The attacker edits the resource or configuration file, for example a web.xml file used to configure security permissions for a J2EE app server, adding role name "public" grants all users with the public role the ability to use the administration functionality. The server trusts its configuration file to be correct, but when they are manipulated, the attacker gains full control.
  • Blue Boxing
    This type of attack against older telephone switches and trunks has been around for decades. A tone is sent by an adversary to impersonate a supervisor signal which has the effect of rerouting or usurping command of the line. While the US infrastructure proper may not contain widespread vulnerabilities to this type of attack, many companies are connected globally through call centers and business process outsourcing. These international systems may be operated in countries which have not upgraded Telco infrastructure and so are vulnerable to Blue boxing. Blue boxing is a result of failure on the part of the system to enforce strong authorization for administrative functions. While the infrastructure is different than standard current applications like web applications, there are historical lessons to be learned to upgrade the access control for administrative functions.
  • Restful Privilege Elevation
    Rest uses standard HTTP (Get, Put, Delete) style permissions methods, but these are not necessarily correlated generally with back end programs. Strict interpretation of HTTP get methods means that these HTTP Get services should not be used to delete information on the server, but there is no access control mechanism to back up this logic. This means that unless the services are properly ACL'd and the application's service implementation are following these guidelines then an HTTP request can easily execute a delete or update on the server side. The attacker identifies a HTTP Get URL such as http://victimsite/updateOrder, which calls out to a program to update orders on a database or other resource. The URL is not idempotent so the request can be submitted multiple times by the attacker, additionally, the attacker may be able to exploit the URL published as a Get method that actually performs updates (instead of merely retrieving data). This may result in malicious or inadvertent altering of data on the server.
  • Target Programs with Elevated Privileges
    This attack targets programs running with elevated privileges. The attacker would try to leverage a bug in the running program and get arbitrary code to execute with elevated privileges. For instance an attacker would look for programs that write to the system directories or registry keys (such as HKLM, which stores a number of critical Windows environment variables). These programs are typically running with elevated privileges and have usually not been designed with security in mind. Such programs are excellent exploit targets because they yield lots of power when they break. The malicious user try to execute its code at the same level as a privileged system call.
  • Manipulating Input to File System Calls
    An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.
Access
VectorComplexityAuthentication
NETWORK LOW NONE
Impact
ConfidentialityIntegrityAvailability
NONE PARTIAL NONE
nessus via4
  • NASL family Fedora Local Security Checks
    NASL id FEDORA_2016-E1589894E8.NASL
    description New upstream release Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2016-10-18
    plugin id 93492
    published 2016-09-15
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=93492
    title Fedora 24 : gnutls (2016-e1589894e8)
  • NASL family CentOS Local Security Checks
    NASL id CENTOS_RHSA-2017-2292.NASL
    description An update for gnutls is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorithms and protocols such as SSL, TLS, and DTLS. The following packages have been upgraded to a later upstream version: gnutls (3.3.26). (BZ#1378373) Security Fix(es) : * A double-free flaw was found in the way GnuTLS parsed certain X.509 certificates with Proxy Certificate Information extension. An attacker could create a specially crafted certificate which, when processed by an application compiled against GnuTLS, could cause that application to crash. (CVE-2017-5334) * Multiple flaws were found in the way gnutls processed OpenPGP certificates. An attacker could create specially crafted OpenPGP certificates which, when parsed by gnutls, would cause it to crash. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337, CVE-2017-7869) * A NULL pointer dereference flaw was found in the way GnuTLS processed ClientHello messages with status_request extension. A remote attacker could use this flaw to cause an application compiled with GnuTLS to crash. (CVE-2017-7507) * A flaw was found in the way GnuTLS validated certificates using OCSP responses. This could falsely report a certificate as valid under certain circumstances. (CVE-2016-7444) The CVE-2017-7507 issue was discovered by Hubert Kario (Red Hat QE BaseOS Security team). Additional Changes : For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.4 Release Notes linked from the References section.
    last seen 2019-02-21
    modified 2018-11-10
    plugin id 102759
    published 2017-08-25
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=102759
    title CentOS 7 : gnutls (CESA-2017:2292)
  • NASL family Huawei Local Security Checks
    NASL id EULEROS_SA-2017-1203.NASL
    description According to the versions of the gnutls packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities : - A double-free flaw was found in the way GnuTLS parsed certain X.509 certificates with Proxy Certificate Information extension. An attacker could create a specially-crafted certificate which, when processed by an application compiled against GnuTLS, could cause that application to crash. (CVE-2017-5334) - Multiple flaws were found in the way gnutls processed OpenPGP certificates. An attacker could create specially crafted OpenPGP certificates which, when parsed by gnutls, would cause it to crash. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337, CVE-2017-7869) - A null pointer dereference flaw was found in the way GnuTLS processed ClientHello messages with status_request extension. A remote attacker could use this flaw to cause an application compiled with GnuTLS to crash. (CVE-2017-7507) - A flaw was found in the way GnuTLS validated certificates using OCSP responses. This could falsely report a certificate as valid under certain circumstances. (CVE-2016-7444) Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2018-11-14
    plugin id 103061
    published 2017-09-11
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=103061
    title EulerOS 2.0 SP1 : gnutls (EulerOS-SA-2017-1203)
  • NASL family Fedora Local Security Checks
    NASL id FEDORA_2016-A1E5B2331A.NASL
    description https://lists.gnupg.org/pipermail/gnutls-devel/2016-September/008153.h tml Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2016-11-15
    plugin id 94844
    published 2016-11-15
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=94844
    title Fedora 25 : mingw-gnutls (2016-a1e5b2331a)
  • NASL family Red Hat Local Security Checks
    NASL id REDHAT-RHSA-2017-2292.NASL
    description An update for gnutls is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorithms and protocols such as SSL, TLS, and DTLS. The following packages have been upgraded to a later upstream version: gnutls (3.3.26). (BZ#1378373) Security Fix(es) : * A double-free flaw was found in the way GnuTLS parsed certain X.509 certificates with Proxy Certificate Information extension. An attacker could create a specially crafted certificate which, when processed by an application compiled against GnuTLS, could cause that application to crash. (CVE-2017-5334) * Multiple flaws were found in the way gnutls processed OpenPGP certificates. An attacker could create specially crafted OpenPGP certificates which, when parsed by gnutls, would cause it to crash. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337, CVE-2017-7869) * A NULL pointer dereference flaw was found in the way GnuTLS processed ClientHello messages with status_request extension. A remote attacker could use this flaw to cause an application compiled with GnuTLS to crash. (CVE-2017-7507) * A flaw was found in the way GnuTLS validated certificates using OCSP responses. This could falsely report a certificate as valid under certain circumstances. (CVE-2016-7444) The CVE-2017-7507 issue was discovered by Hubert Kario (Red Hat QE BaseOS Security team). Additional Changes : For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.4 Release Notes linked from the References section.
    last seen 2019-02-21
    modified 2018-11-26
    plugin id 102116
    published 2017-08-02
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=102116
    title RHEL 7 : gnutls (RHSA-2017:2292)
  • NASL family Scientific Linux Local Security Checks
    NASL id SL_20170801_GNUTLS_ON_SL7_X.NASL
    description The following packages have been upgraded to a later upstream version: gnutls (3.3.26). Security Fix(es) : - A double-free flaw was found in the way GnuTLS parsed certain X.509 certificates with Proxy Certificate Information extension. An attacker could create a specially crafted certificate which, when processed by an application compiled against GnuTLS, could cause that application to crash. (CVE-2017-5334) - Multiple flaws were found in the way gnutls processed OpenPGP certificates. An attacker could create specially crafted OpenPGP certificates which, when parsed by gnutls, would cause it to crash. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337, CVE-2017-7869) - A NULL pointer dereference flaw was found in the way GnuTLS processed ClientHello messages with status_request extension. A remote attacker could use this flaw to cause an application compiled with GnuTLS to crash. (CVE-2017-7507) - A flaw was found in the way GnuTLS validated certificates using OCSP responses. This could falsely report a certificate as valid under certain circumstances. (CVE-2016-7444)
    last seen 2019-02-21
    modified 2018-12-27
    plugin id 102642
    published 2017-08-22
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=102642
    title Scientific Linux Security Update : gnutls on SL7.x x86_64
  • NASL family Oracle Linux Local Security Checks
    NASL id ORACLELINUX_ELSA-2017-2292.NASL
    description From Red Hat Security Advisory 2017:2292 : An update for gnutls is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorithms and protocols such as SSL, TLS, and DTLS. The following packages have been upgraded to a later upstream version: gnutls (3.3.26). (BZ#1378373) Security Fix(es) : * A double-free flaw was found in the way GnuTLS parsed certain X.509 certificates with Proxy Certificate Information extension. An attacker could create a specially crafted certificate which, when processed by an application compiled against GnuTLS, could cause that application to crash. (CVE-2017-5334) * Multiple flaws were found in the way gnutls processed OpenPGP certificates. An attacker could create specially crafted OpenPGP certificates which, when parsed by gnutls, would cause it to crash. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337, CVE-2017-7869) * A NULL pointer dereference flaw was found in the way GnuTLS processed ClientHello messages with status_request extension. A remote attacker could use this flaw to cause an application compiled with GnuTLS to crash. (CVE-2017-7507) * A flaw was found in the way GnuTLS validated certificates using OCSP responses. This could falsely report a certificate as valid under certain circumstances. (CVE-2016-7444) The CVE-2017-7507 issue was discovered by Hubert Kario (Red Hat QE BaseOS Security team). Additional Changes : For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.4 Release Notes linked from the References section.
    last seen 2019-02-21
    modified 2018-07-25
    plugin id 102303
    published 2017-08-09
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=102303
    title Oracle Linux 7 : gnutls (ELSA-2017-2292)
  • NASL family Huawei Local Security Checks
    NASL id EULEROS_SA-2017-1204.NASL
    description According to the versions of the gnutls packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities : - A double-free flaw was found in the way GnuTLS parsed certain X.509 certificates with Proxy Certificate Information extension. An attacker could create a specially-crafted certificate which, when processed by an application compiled against GnuTLS, could cause that application to crash. (CVE-2017-5334) - Multiple flaws were found in the way gnutls processed OpenPGP certificates. An attacker could create specially crafted OpenPGP certificates which, when parsed by gnutls, would cause it to crash. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337, CVE-2017-7869) - A null pointer dereference flaw was found in the way GnuTLS processed ClientHello messages with status_request extension. A remote attacker could use this flaw to cause an application compiled with GnuTLS to crash. (CVE-2017-7507) - A flaw was found in the way GnuTLS validated certificates using OCSP responses. This could falsely report a certificate as valid under certain circumstances. (CVE-2016-7444) Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2018-11-14
    plugin id 103062
    published 2017-09-11
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=103062
    title EulerOS 2.0 SP2 : gnutls (EulerOS-SA-2017-1204)
  • NASL family Fedora Local Security Checks
    NASL id FEDORA_2016-2EDB9ADEC8.NASL
    description New upstream release Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2016-10-18
    plugin id 93489
    published 2016-09-15
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=93489
    title Fedora 23 : gnutls (2016-2edb9adec8)
  • NASL family SuSE Local Security Checks
    NASL id SUSE_SU-2017-0348-1.NASL
    description This update for gnutls fixes the following security issues : - GnuTLS could have crashed when processing maliciously crafted OpenPGP certificates (GNUTLS-SA-2017-2, bsc#1018832, CVE-2017-5335, CVE-2017-5337, CVE-2017-5336) - GnuTLS could have falsely accepted certificates when using OCSP (GNUTLS-SA-2016-3, bsc#999646, CVE-2016-7444) - GnuTLS could have suffered from 100% CPU load DoS attacks by using SSL alert packets during the handshake (bsc#1005879, CVE-2016-8610) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2018-11-30
    plugin id 96950
    published 2017-02-02
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=96950
    title SUSE SLED12 / SLES12 Security Update : gnutls (SUSE-SU-2017:0348-1)
  • NASL family Ubuntu Local Security Checks
    NASL id UBUNTU_USN-3183-1.NASL
    description Stefan Buehler discovered that GnuTLS incorrectly verified the serial length of OCSP responses. A remote attacker could possibly use this issue to bypass certain certificate validation measures. This issue only applied to Ubuntu 16.04 LTS. (CVE-2016-7444) Shi Lei discovered that GnuTLS incorrectly handled certain warning alerts. A remote attacker could possibly use this issue to cause GnuTLS to hang, resulting in a denial of service. This issue has only been addressed in Ubuntu 16.04 LTS and Ubuntu 16.10. (CVE-2016-8610) It was discovered that GnuTLS incorrectly decoded X.509 certificates with a Proxy Certificate Information extension. A remote attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 16.04 LTS and Ubuntu 16.10. (CVE-2017-5334) It was discovered that GnuTLS incorrectly handled certain OpenPGP certificates. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337). Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2018-12-01
    plugin id 96952
    published 2017-02-02
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=96952
    title Ubuntu 12.04 LTS / 14.04 LTS / 16.04 LTS / 16.10 : gnutls26, gnutls28 vulnerabilities (USN-3183-1)
  • NASL family SuSE Local Security Checks
    NASL id OPENSUSE-2017-207.NASL
    description This update for gnutls fixes the following security issues : - GnuTLS could have crashed when processing maliciously crafted OpenPGP certificates (GNUTLS-SA-2017-2, bsc#1018832, CVE-2017-5335, CVE-2017-5337, CVE-2017-5336) - GnuTLS could have falsely accepted certificates when using OCSP (GNUTLS-SA-2016-3, bsc#999646, CVE-2016-7444) - GnuTLS could have suffered from 100% CPU load DoS attacks by using SSL alert packets during the handshake (bsc#1005879, CVE-2016-8610) This update was imported from the SUSE:SLE-12:Update update project.
    last seen 2019-02-21
    modified 2018-01-26
    plugin id 97004
    published 2017-02-06
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=97004
    title openSUSE Security Update : gnutls (openSUSE-2017-207)
  • NASL family Fedora Local Security Checks
    NASL id FEDORA_2016-CAFDFDF58C.NASL
    description New upstream release Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2016-11-15
    plugin id 94862
    published 2016-11-15
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=94862
    title Fedora 25 : gnutls (2016-cafdfdf58c)
  • NASL family PhotonOS Local Security Checks
    NASL id PHOTONOS_PHSA-2017-0015_GNUTLS.NASL
    description An update of the gnutls package has been released.
    last seen 2019-02-08
    modified 2019-02-07
    plugin id 121688
    published 2019-02-07
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121688
    title Photon OS 1.0: Gnutls PHSA-2017-0015
  • NASL family Ubuntu Local Security Checks
    NASL id UBUNTU_USN-3183-2.NASL
    description USN-3183-1 fixed CVE-2016-8610 in GnuTLS in Ubuntu 16.04 LTS and Ubuntu 16.10. This update provides the corresponding update for Ubuntu 12.04 LTS and Ubuntu 14.04 LTS. Stefan Buehler discovered that GnuTLS incorrectly verified the serial length of OCSP responses. A remote attacker could possibly use this issue to bypass certain certificate validation measures. This issue only applied to Ubuntu 16.04 LTS. (CVE-2016-7444) Shi Lei discovered that GnuTLS incorrectly handled certain warning alerts. A remote attacker could possibly use this issue to cause GnuTLS to hang, resulting in a denial of service. This issue has only been addressed in Ubuntu 16.04 LTS and Ubuntu 16.10. (CVE-2016-8610) It was discovered that GnuTLS incorrectly decoded X.509 certificates with a Proxy Certificate Information extension. A remote attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 16.04 LTS and Ubuntu 16.10. (CVE-2017-5334) It was discovered that GnuTLS incorrectly handled certain OpenPGP certificates. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337). Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2018-12-01
    plugin id 97853
    published 2017-03-21
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=97853
    title Ubuntu 12.04 LTS / 14.04 LTS : gnutls26 vulnerability (USN-3183-2)
  • NASL family PhotonOS Local Security Checks
    NASL id PHOTONOS_PHSA-2017-0015.NASL
    description An update of [freetype2,tar,gnutls,linux] packages for PhotonOS has been released.
    last seen 2019-02-21
    modified 2019-02-07
    plugin id 111864
    published 2018-08-17
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=111864
    title Photon OS 1.0: Freetype2 / Gnutls / Linux / Tar PHSA-2017-0015 (deprecated)
redhat via4
advisories
rhsa
id RHSA-2017:2292
rpms
  • gnutls-0:3.3.26-9.el7
  • gnutls-c++-0:3.3.26-9.el7
  • gnutls-dane-0:3.3.26-9.el7
  • gnutls-devel-0:3.3.26-9.el7
  • gnutls-utils-0:3.3.26-9.el7
refmap via4
bid 92893
confirm
mlist [gnutls-devel] 20160902 OCSP certificate check
suse openSUSE-SU-2017:0386
Last major update 24-03-2017 - 21:59
Published 27-09-2016 - 11:59
Last modified 04-01-2018 - 21:31
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