Vulnerabilities > CVE-2016-2194 - 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
The ressol function in Botan before 1.10.11 and 1.11.x before 1.11.27 allows remote attackers to cause a denial of service (infinite loop) via unspecified input to the OS2ECP function, related to a composite modulus.
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 Gentoo Local Security Checks NASL id GENTOO_GLSA-201612-38.NASL description The remote host is affected by the vulnerability described in GLSA-201612-38 (Botan: Multiple vulnerabilities) Multiple vulnerabilities have been discovered in Botan. Please review the CVE identifiers referenced below for details. Impact : A remote attacker could possibly execute arbitrary code with the privileges of the process, 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 95741 published 2016-12-13 reporter This script is Copyright (C) 2016 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/95741 title GLSA-201612-38 : Botan: Multiple vulnerabilities code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Gentoo Linux Security Advisory GLSA 201612-38. # # The advisory text is Copyright (C) 2001-2016 Gentoo Foundation, Inc. # and licensed under the Creative Commons - Attribution / Share Alike # license. See http://creativecommons.org/licenses/by-sa/3.0/ # include("compat.inc"); if (description) { script_id(95741); script_version("$Revision: 3.1 $"); script_cvs_date("$Date: 2016/12/13 18:01:19 $"); script_cve_id("CVE-2016-2194", "CVE-2016-2195"); script_xref(name:"GLSA", value:"201612-38"); script_name(english:"GLSA-201612-38 : Botan: Multiple vulnerabilities"); script_summary(english:"Checks for updated package(s) in /var/db/pkg"); script_set_attribute( attribute:"synopsis", value: "The remote Gentoo host is missing one or more security-related patches." ); script_set_attribute( attribute:"description", value: "The remote host is affected by the vulnerability described in GLSA-201612-38 (Botan: Multiple vulnerabilities) Multiple vulnerabilities have been discovered in Botan. Please review the CVE identifiers referenced below for details. Impact : A remote attacker could possibly execute arbitrary code with the privileges of the process, or cause a Denial of Service condition. Workaround : There is no known workaround at this time." ); script_set_attribute( attribute:"see_also", value:"https://security.gentoo.org/glsa/201612-38" ); script_set_attribute( attribute:"solution", value: "All Botan users should upgrade to the latest version: # emerge --sync # emerge --ask --oneshot --verbose '>=dev-libs/botan-1.10.12'" ); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:botan"); script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux"); script_set_attribute(attribute:"patch_publication_date", value:"2016/12/13"); script_set_attribute(attribute:"plugin_publication_date", value:"2016/12/13"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2016 Tenable Network Security, Inc."); script_family(english:"Gentoo Local Security Checks"); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list"); exit(0); } include("audit.inc"); include("global_settings.inc"); include("qpkg.inc"); if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED); if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo"); if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING); flag = 0; if (qpkg_check(package:"dev-libs/botan", unaffected:make_list("ge 1.10.12"), vulnerable:make_list("lt 1.10.12"))) flag++; if (flag) { if (report_verbosity > 0) security_hole(port:0, extra:qpkg_report_get()); else security_hole(0); exit(0); } else { tested = qpkg_tests_get(); if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested); else audit(AUDIT_PACKAGE_NOT_INSTALLED, "Botan"); }
NASL family Debian Local Security Checks NASL id DEBIAN_DSA-3565.NASL description Several security vulnerabilities were found in botan1.10, a C++ library which provides support for many common cryptographic operations, including encryption, authentication, X.509v3 certificates and CRLs. - CVE-2015-5726 The BER decoder would crash due to reading from offset 0 of an empty vector if it encountered a BIT STRING which did not contain any data at all. This can be used to easily crash applications reading untrusted ASN.1 data, but does not seem exploitable for code execution. - CVE-2015-5727 The BER decoder would allocate a fairly arbitrary amount of memory in a length field, even if there was no chance the read request would succeed. This might cause the process to run out of memory or invoke the OOM killer. - CVE-2015-7827 Use constant time PKCS #1 unpadding to avoid possible side channel attack against RSA decryption - CVE-2016-2194 Infinite loop in modular square root algorithm. The ressol function implementing the Tonelli-Shanks algorithm for finding square roots could be sent into a nearly infinite loop due to a misplaced conditional check. This could occur if a composite modulus is provided, as this algorithm is only defined for primes. This function is exposed to attacker controlled input via the OS2ECP function during ECC point decompression. - CVE-2016-2195 Fix Heap overflow on invalid ECC point. - CVE-2016-2849 Use constant time modular inverse algorithm to avoid possible side channel attack against ECDSA. last seen 2020-06-01 modified 2020-06-02 plugin id 90841 published 2016-05-03 reporter This script is Copyright (C) 2016-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/90841 title Debian DSA-3565-1 : botan1.10 - security update NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_4CD9B19FF66D11E5B94C001999F8D30B.NASL description The botan developers reports : Infinite loop in modular square root algorithm - The ressol function implements the Tonelli-Shanks algorithm for finding square roots could be sent into a nearly infinite loop due to a misplaced conditional check. This could occur if a composite modulus is provided, as this algorithm is only defined for primes. This function is exposed to attacker controlled input via the OS2ECP function during ECC point decompression. Heap overflow on invalid ECC point - The PointGFp constructor did not check that the affine coordinate arguments were less than the prime, but then in curve multiplication assumed that both arguments if multiplied would fit into an integer twice the size of the prime. The bigint_mul and bigint_sqr functions received the size of the output buffer, but only used it to dispatch to a faster algorithm in cases where there was sufficient output space to call an unrolled multiplication function. The result is a heap overflow accessible via ECC point decoding, which accepted untrusted inputs. This is likely exploitable for remote code execution. On systems which use the mlock pool allocator, it would allow an attacker to overwrite memory held in secure_vector objects. After this point the write will hit the guard page at the end of the mmapped region so it probably could not be used for code execution directly, but would allow overwriting adjacent key material. last seen 2020-06-01 modified 2020-06-02 plugin id 90287 published 2016-04-01 reporter This script is Copyright (C) 2016-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/90287 title FreeBSD : Multiple vulnerabilities in Botan (4cd9b19f-f66d-11e5-b94c-001999f8d30b) NASL family Fedora Local Security Checks NASL id FEDORA_2016-1C08D77B96.NASL description Security fix for CVE-2016-2194, CVE-2016-2195, CVE-2016-2196 Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. last seen 2020-06-05 modified 2016-03-04 plugin id 89488 published 2016-03-04 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/89488 title Fedora 22 : botan-1.10.12-1.fc22 / code-editor-2.8.1-13.fc22 / monotone-1.1-13.fc22 / etc (2016-1c08d77b96) NASL family Fedora Local Security Checks NASL id FEDORA_2016-FB9B356B74.NASL description Security fix for CVE-2016-2194, CVE-2016-2195, CVE-2016-2196 Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. last seen 2020-06-05 modified 2016-03-04 plugin id 89646 published 2016-03-04 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/89646 title Fedora 23 : botan-1.10.12-1.fc23 / code-editor-2.8.1-13.fc23 / monotone-1.1-13.fc23 / etc (2016-fb9b356b74)