Vulnerabilities > CVE-2016-4579 - Improper Input Validation vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
Libksba before 1.3.4 allows remote attackers to cause a denial of service (out-of-bounds read and crash) via unspecified vectors, related to the "returned length of the object from _ksba_ber_parse_tl."
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Buffer Overflow via Environment Variables This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
- Server Side Include (SSI) Injection An attacker can use Server Side Include (SSI) Injection to send code to a web application that then gets executed by the web server. Doing so enables the attacker to achieve similar results to Cross Site Scripting, viz., arbitrary code execution and information disclosure, albeit on a more limited scale, since the SSI directives are nowhere near as powerful as a full-fledged scripting language. Nonetheless, the attacker can conveniently gain access to sensitive files, such as password files, and execute shell commands.
- Cross Zone Scripting An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security. In a zone-based model, pages belong to one of a set of zones corresponding to the level of privilege assigned to that page. Pages in an untrusted zone would have a lesser level of access to the system and/or be restricted in the types of executable content it was allowed to invoke. In a cross-zone scripting attack, a page that should be assigned to a less privileged zone is granted the privileges of a more trusted zone. This can be accomplished by exploiting bugs in the browser, exploiting incorrect configuration in the zone controls, through a cross-site scripting attack that causes the attackers' content to be treated as coming from a more trusted page, or by leveraging some piece of system functionality that is accessible from both the trusted and less trusted zone. This attack differs from "Restful Privilege Escalation" in that the latter correlates to the inadequate securing of RESTful access methods (such as HTTP DELETE) on the server, while cross-zone scripting attacks the concept of security zones as implemented by a browser.
- Cross Site Scripting through Log Files An attacker may leverage a system weakness where logs are susceptible to log injection to insert scripts into the system's logs. If these logs are later viewed by an administrator through a thin administrative interface and the log data is not properly HTML encoded before being written to the page, the attackers' scripts stored in the log will be executed in the administrative interface with potentially serious consequences. This attack pattern is really a combination of two other attack patterns: log injection and stored cross site scripting.
- Command Line Execution through SQL Injection An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.
Nessus
NASL family Fedora Local Security Checks NASL id FEDORA_2016-28A56C76C1.NASL description Security fix for minor security issues CVE-2016-4574, CVE-2016-4579. 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 2020-06-05 modified 2016-07-14 plugin id 92072 published 2016-07-14 reporter This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/92072 title Fedora 22 : libksba (2016-28a56c76c1) code #%NASL_MIN_LEVEL 80502 # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Fedora Security Advisory FEDORA-2016-28a56c76c1. # include("compat.inc"); if (description) { script_id(92072); script_version("1.4"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04"); script_cve_id("CVE-2016-4574", "CVE-2016-4579"); script_xref(name:"FEDORA", value:"2016-28a56c76c1"); script_name(english:"Fedora 22 : libksba (2016-28a56c76c1)"); script_summary(english:"Checks rpm output for the updated package."); script_set_attribute( attribute:"synopsis", value:"The remote Fedora host is missing a security update." ); script_set_attribute( attribute:"description", value: "Security fix for minor security issues CVE-2016-4574, CVE-2016-4579. 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." ); script_set_attribute( attribute:"see_also", value:"https://bodhi.fedoraproject.org/updates/FEDORA-2016-28a56c76c1" ); script_set_attribute( attribute:"solution", value:"Update the affected libksba package." ); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:libksba"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:22"); script_set_attribute(attribute:"vuln_publication_date", value:"2016/06/13"); script_set_attribute(attribute:"patch_publication_date", value:"2016/05/20"); script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/14"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof."); script_family(english:"Fedora Local Security Checks"); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list"); exit(0); } include("audit.inc"); include("global_settings.inc"); include("rpm.inc"); if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED); release = get_kb_item("Host/RedHat/release"); if (isnull(release) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora"); os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release); if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora"); os_ver = os_ver[1]; if (! preg(pattern:"^22([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 22", "Fedora " + os_ver); if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu); flag = 0; if (rpm_check(release:"FC22", reference:"libksba-1.3.4-1.fc22")) flag++; if (flag) { security_report_v4( port : 0, severity : SECURITY_WARNING, extra : rpm_report_get() ); exit(0); } else { tested = pkg_tests_get(); if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested); else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libksba"); }
NASL family SuSE Local Security Checks NASL id OPENSUSE-2016-697.NASL description This update for libksba fixes the following issues : - CVE-2016-4579: Out-of-bounds read in _ksba_ber_parse_tl() - CVE-2016-4574: two OOB read access bugs (remote DoS) (bsc#979261) Also adding reliability fixes from v1.3.4. This update was imported from the SUSE:SLE-12:Update update project. last seen 2020-06-05 modified 2016-06-09 plugin id 91532 published 2016-06-09 reporter This script is Copyright (C) 2016-2020 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/91532 title openSUSE Security Update : libksba (openSUSE-2016-697) NASL family Ubuntu Local Security Checks NASL id UBUNTU_USN-2982-1.NASL description Hanno Bock discovered that Libksba incorrectly handled decoding certain BER data. An attacker could use this issue to cause Libksba to crash, resulting in a denial of service. This issue only applied to Ubunt 12.04 LTS and Ubuntu 14.04 LTS. (CVE-2016-4353) Hanno Bock discovered that Libksba incorrectly handled decoding certain BER data. An attacker could use this issue to cause Libksba to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only applied to Ubunt 12.04 LTS and Ubuntu 14.04 LTS. (CVE-2016-4354, CVE-2016-4355) Hanno Bock discovered that Libksba incorrectly handled incorrect utf-8 strings when decoding certain DN data. An attacker could use this issue to cause Libksba to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only applied to Ubunt 12.04 LTS and Ubuntu 14.04 LTS. (CVE-2016-4356) Pascal Cuoq discovered that Libksba incorrectly handled incorrect utf-8 strings when decoding certain DN data. An attacker could use this issue to cause Libksba to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2016-4574) Pascal Cuoq discovered that Libksba incorrectly handled decoding certain data. An attacker could use this issue to cause Libksba to crash, resulting in a denial of service. (CVE-2016-4579). 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 2020-06-01 modified 2020-06-02 plugin id 91220 published 2016-05-18 reporter Ubuntu Security Notice (C) 2016-2019 Canonical, Inc. / NASL script (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/91220 title Ubuntu 12.04 LTS / 14.04 LTS / 15.10 / 16.04 LTS : libksba vulnerabilities (USN-2982-1) NASL family SuSE Local Security Checks NASL id SUSE_SU-2016-1509-1.NASL description This update for libksba fixes the following issues : - CVE-2016-4579: Out-of-bounds read in _ksba_ber_parse_tl() - CVE-2016-4574: two OOB read access bugs (remote DoS) (bsc#979261) Also adding reliability fixes from v1.3.4. 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 2020-06-01 modified 2020-06-02 plugin id 91653 published 2016-06-17 reporter This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/91653 title SUSE SLES11 Security Update : libksba (SUSE-SU-2016:1509-1) NASL family SuSE Local Security Checks NASL id SUSE_SU-2016-1510-1.NASL description This update for libksba fixes the following issues : - CVE-2016-4579: Out-of-bounds read in _ksba_ber_parse_tl() - CVE-2016-4574: two OOB read access bugs (remote DoS) (bsc#979261) Also adding reliability fixes from v1.3.4. 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 2020-06-01 modified 2020-06-02 plugin id 91654 published 2016-06-17 reporter This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/91654 title SUSE SLED12 / SLES12 Security Update : libksba (SUSE-SU-2016:1510-1) NASL family Fedora Local Security Checks NASL id FEDORA_2016-FD26F713E7.NASL description Security fix for minor security issues CVE-2016-4574, CVE-2016-4579. 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 2020-06-05 modified 2016-07-14 plugin id 92214 published 2016-07-14 reporter This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/92214 title Fedora 23 : libksba (2016-fd26f713e7) NASL family Fedora Local Security Checks NASL id FEDORA_2016-1BCEC8B80D.NASL description Security fix for minor security issues CVE-2016-4574, CVE-2016-4579. 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 2020-06-05 modified 2016-07-14 plugin id 92064 published 2016-07-14 reporter This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/92064 title Fedora 24 : libksba (2016-1bcec8b80d) NASL family Gentoo Local Security Checks NASL id GENTOO_GLSA-201706-22.NASL description The remote host is affected by the vulnerability described in GLSA-201706-22 (libksba: Denial of Service and information disclosure) It was found that an unproportionate amount of memory is allocated when parsing crafted certificates in libskba, which may lead to Denial of Service condition. Moreover in libksba 1.3.4, allocated memory is uninitialized and could potentially contain sensitive data left in freed memory block. Impact : A remote attacker, able to interact with an libksba-based application, could possibly obtain sensitive information or cause a Denial of Service condition. Workaround : There is no known workaround at this time. last seen 2020-06-01 modified 2020-06-02 plugin id 101017 published 2017-06-23 reporter This script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/101017 title GLSA-201706-22 : libksba: Denial of Service and information disclosure NASL family Amazon Linux Local Security Checks NASL id ALA_ALAS-2016-712.NASL description The following security-related issues were resolved : Incomplete fix for CVE-2016-4356 (CVE-2016-4574) Out-of-bounds read in _ksba_ber_parse_tl (CVE-2016-4579) last seen 2020-06-01 modified 2020-06-02 plugin id 91471 published 2016-06-06 reporter This script is Copyright (C) 2016-2018 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/91471 title Amazon Linux AMI : libksba (ALAS-2016-712) NASL family Debian Local Security Checks NASL id DEBIAN_DLA-470.NASL description It was discovered that there was a possible read access beyond a buffer vulnerability in libksba, a X.509 and CMS certificate support library. The returned length of the object from _ksba_ber_parse_tl (ti.length) was not always checked against the actual buffer length, thus leading to a read access after the end of the buffer and thus a SEGV. For Debian 7 last seen 2020-03-17 modified 2016-05-16 plugin id 91132 published 2016-05-16 reporter This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/91132 title Debian DLA-470-1 : libksba security update
References
- http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libksba.git%3Ba=commit%3Bh=a7eed17a0b2a1c09ef986f3b4b323cd31cea2b64
- http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libksba.git%3Ba=commit%3Bh=a7eed17a0b2a1c09ef986f3b4b323cd31cea2b64
- http://lists.opensuse.org/opensuse-updates/2016-06/msg00028.html
- http://lists.opensuse.org/opensuse-updates/2016-06/msg00028.html
- http://www.openwall.com/lists/oss-security/2016/05/10/8
- http://www.openwall.com/lists/oss-security/2016/05/10/8
- http://www.openwall.com/lists/oss-security/2016/05/11/10
- http://www.openwall.com/lists/oss-security/2016/05/11/10
- http://www.ubuntu.com/usn/USN-2982-1
- http://www.ubuntu.com/usn/USN-2982-1
- https://security.gentoo.org/glsa/201706-22
- https://security.gentoo.org/glsa/201706-22