Vulnerabilities > CVE-2012-6711 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in multiple products
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
A heap-based buffer overflow exists in GNU Bash before 4.3 when wide characters, not supported by the current locale set in the LC_CTYPE environment variable, are printed through the echo built-in function. A local attacker, who can provide data to print through the "echo -e" built-in function, may use this flaw to crash a script or execute code with the privileges of the bash process. This occurs because ansicstr() in lib/sh/strtrans.c mishandles u32cconv().
Vulnerable Configurations
Part | Description | Count |
---|---|---|
Application | 3 | |
OS | 1 |
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.
- Overflow Buffers Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
- Client-side Injection-induced Buffer Overflow This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
- Filter Failure through Buffer Overflow In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
- MIME Conversion An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.
Nessus
NASL family PhotonOS Local Security Checks NASL id PHOTONOS_PHSA-2019-1_0-0255_BASH.NASL description An update of the bash package has been released. last seen 2020-06-01 modified 2020-06-02 plugin id 129681 published 2019-10-07 reporter This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/129681 title Photon OS 1.0: Bash PHSA-2019-1.0-0255 code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from VMware Security Advisory PHSA-2019-1.0-0255. The text # itself is copyright (C) VMware, Inc. include("compat.inc"); if (description) { script_id(129681); script_version("1.2"); script_cvs_date("Date: 2019/12/19"); script_cve_id("CVE-2012-6711"); script_name(english:"Photon OS 1.0: Bash PHSA-2019-1.0-0255"); script_set_attribute(attribute:"synopsis", value: "The remote PhotonOS host is missing multiple security updates."); script_set_attribute(attribute:"description", value: "An update of the bash package has been released."); script_set_attribute(attribute:"see_also", value:"https://github.com/vmware/photon/wiki/Security-Updates-1.0-255.md"); script_set_attribute(attribute:"solution", value: "Update the affected Linux packages."); script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P"); script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C"); script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"); script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C"); script_set_attribute(attribute:"cvss_score_source", value:"CVE-2012-6711"); script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available"); script_set_attribute(attribute:"vuln_publication_date", value:"2019/06/18"); script_set_attribute(attribute:"patch_publication_date", value:"2019/10/01"); script_set_attribute(attribute:"plugin_publication_date", value:"2019/10/07"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:vmware:photonos:bash"); script_set_attribute(attribute:"cpe", value:"cpe:/o:vmware:photonos:1.0"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_family(english:"PhotonOS Local Security Checks"); script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof."); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/PhotonOS/release", "Host/PhotonOS/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/PhotonOS/release"); if (isnull(release) || release !~ "^VMware Photon") audit(AUDIT_OS_NOT, "PhotonOS"); if (release !~ "^VMware Photon (?:Linux|OS) 1\.0(\D|$)") audit(AUDIT_OS_NOT, "PhotonOS 1.0"); if (!get_kb_item("Host/PhotonOS/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "PhotonOS", cpu); flag = 0; if (rpm_check(release:"PhotonOS-1.0", reference:"bash-4.3.48-4.ph1")) flag++; if (rpm_check(release:"PhotonOS-1.0", reference:"bash-debuginfo-4.3.48-4.ph1")) flag++; if (rpm_check(release:"PhotonOS-1.0", reference:"bash-lang-4.3.48-4.ph1")) 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, "bash"); }
NASL family Huawei Local Security Checks NASL id EULEROS_SA-2019-1911.NASL description According to the version of the bash package installed, the EulerOS installation on the remote host is affected by the following vulnerability : - A heap-based buffer overflow was discovered in bash when wide characters, not supported by the current locale set in LC_CTYPE environment variable, are printed through the echo built-in function. A local attacker, who can provide data to print through the `echo -e` built-in function, may use this flaw to crash a script or execute code with the privileges of the bash process.(CVE-2012-6711) 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 2020-05-08 modified 2019-09-16 plugin id 128834 published 2019-09-16 reporter This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/128834 title EulerOS 2.0 SP5 : bash (EulerOS-SA-2019-1911) code # # (C) Tenable Network Security, Inc. # include("compat.inc"); if (description) { script_id(128834); script_version("1.3"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/05/07"); script_cve_id( "CVE-2012-6711" ); script_name(english:"EulerOS 2.0 SP5 : bash (EulerOS-SA-2019-1911)"); script_summary(english:"Checks the rpm output for the updated package."); script_set_attribute(attribute:"synopsis", value: "The remote EulerOS host is missing a security update."); script_set_attribute(attribute:"description", value: "According to the version of the bash package installed, the EulerOS installation on the remote host is affected by the following vulnerability : - A heap-based buffer overflow was discovered in bash when wide characters, not supported by the current locale set in LC_CTYPE environment variable, are printed through the echo built-in function. A local attacker, who can provide data to print through the `echo -e` built-in function, may use this flaw to crash a script or execute code with the privileges of the bash process.(CVE-2012-6711) 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."); # https://developer.huaweicloud.com/ict/en/site-euleros/euleros/security-advisories/EulerOS-SA-2019-1911 script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?36c57f2e"); script_set_attribute(attribute:"solution", value: "Update the affected bash package."); script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P"); script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C"); script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"); script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C"); script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available"); script_set_attribute(attribute:"patch_publication_date", value:"2019/09/12"); script_set_attribute(attribute:"plugin_publication_date", value:"2019/09/16"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:bash"); script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:2.0"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_family(english:"Huawei Local Security Checks"); script_copyright(english:"This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof."); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/EulerOS/release", "Host/EulerOS/rpm-list", "Host/EulerOS/sp"); script_exclude_keys("Host/EulerOS/uvp_version"); 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/EulerOS/release"); if (isnull(release) || release !~ "^EulerOS") audit(AUDIT_OS_NOT, "EulerOS"); if (release !~ "^EulerOS release 2\.0(\D|$)") audit(AUDIT_OS_NOT, "EulerOS 2.0"); sp = get_kb_item("Host/EulerOS/sp"); if (isnull(sp) || sp !~ "^(5)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP5"); uvp = get_kb_item("Host/EulerOS/uvp_version"); if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP5", "EulerOS UVP " + uvp); if (!get_kb_item("Host/EulerOS/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$" && "aarch64" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_ARCH_NOT, "i686 / x86_64", cpu); flag = 0; pkgs = ["bash-4.2.46-30.h8.eulerosv2r7"]; foreach (pkg in pkgs) if (rpm_check(release:"EulerOS-2.0", sp:"5", reference:pkg)) 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, "bash"); }
NASL family SuSE Local Security Checks NASL id SUSE_SU-2019-2976-1.NASL description This update for bash fixes the following issues : CVE-2012-6711: Fixed a heap-based buffer overflow during echo of unsupported characters (bsc#1138676). 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 131071 published 2019-11-15 reporter This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/131071 title SUSE SLES12 Security Update : bash (SUSE-SU-2019:2976-1) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from SUSE update advisory SUSE-SU-2019:2976-1. # The text itself is copyright (C) SUSE. # include("compat.inc"); if (description) { script_id(131071); script_version("1.2"); script_cvs_date("Date: 2019/12/12"); script_cve_id("CVE-2012-6711"); script_name(english:"SUSE SLES12 Security Update : bash (SUSE-SU-2019:2976-1)"); script_summary(english:"Checks rpm output for the updated packages."); script_set_attribute( attribute:"synopsis", value:"The remote SUSE host is missing one or more security updates." ); script_set_attribute( attribute:"description", value: "This update for bash fixes the following issues : CVE-2012-6711: Fixed a heap-based buffer overflow during echo of unsupported characters (bsc#1138676). 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." ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.suse.com/show_bug.cgi?id=1138676" ); script_set_attribute( attribute:"see_also", value:"https://www.suse.com/security/cve/CVE-2012-6711/" ); # https://www.suse.com/support/update/announcement/2019/suse-su-20192976-1/ script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?1fba2497" ); script_set_attribute( attribute:"solution", value: "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or 'zypper patch'. Alternatively you can run the command listed for your product : SUSE Linux Enterprise Server for SAP 12-SP1:zypper in -t patch SUSE-SLE-SAP-12-SP1-2019-2976=1 SUSE Linux Enterprise Server 12-SP1-LTSS:zypper in -t patch SUSE-SLE-SERVER-12-SP1-2019-2976=1" ); script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P"); script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C"); script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"); script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C"); script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:bash"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:bash-debuginfo"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:bash-debugsource"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libreadline6"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libreadline6-debuginfo"); script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:suse_linux:12"); script_set_attribute(attribute:"vuln_publication_date", value:"2019/06/18"); script_set_attribute(attribute:"patch_publication_date", value:"2019/11/14"); script_set_attribute(attribute:"plugin_publication_date", value:"2019/11/15"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof."); script_family(english:"SuSE Local Security Checks"); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/cpu", "Host/SuSE/release", "Host/SuSE/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/SuSE/release"); if (isnull(release) || release !~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "SUSE"); os_ver = pregmatch(pattern: "^(SLE(S|D)\d+)", string:release); if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "SUSE"); os_ver = os_ver[1]; if (! preg(pattern:"^(SLES12)$", string:os_ver)) audit(AUDIT_OS_NOT, "SUSE SLES12", "SUSE " + os_ver); if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if (cpu !~ "^i[3-6]86$" && "x86_64" >!< cpu && "s390x" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "SUSE " + os_ver, cpu); sp = get_kb_item("Host/SuSE/patchlevel"); if (isnull(sp)) sp = "0"; if (os_ver == "SLES12" && (! preg(pattern:"^(1)$", string:sp))) audit(AUDIT_OS_NOT, "SLES12 SP1", os_ver + " SP" + sp); flag = 0; if (rpm_check(release:"SLES12", sp:"1", reference:"bash-4.2-83.6.1")) flag++; if (rpm_check(release:"SLES12", sp:"1", reference:"bash-debuginfo-4.2-83.6.1")) flag++; if (rpm_check(release:"SLES12", sp:"1", reference:"bash-debugsource-4.2-83.6.1")) flag++; if (rpm_check(release:"SLES12", sp:"1", reference:"libreadline6-6.2-83.6.1")) flag++; if (rpm_check(release:"SLES12", sp:"1", reference:"libreadline6-debuginfo-6.2-83.6.1")) flag++; if (rpm_check(release:"SLES12", sp:"1", reference:"libreadline6-32bit-6.2-83.6.1")) flag++; if (rpm_check(release:"SLES12", sp:"1", reference:"libreadline6-debuginfo-32bit-6.2-83.6.1")) flag++; if (flag) { if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get()); else security_warning(0); exit(0); } else { tested = pkg_tests_get(); if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested); else audit(AUDIT_PACKAGE_NOT_INSTALLED, "bash"); }
NASL family Huawei Local Security Checks NASL id EULEROS_SA-2019-1942.NASL description According to the version of the bash package installed, the EulerOS Virtualization for ARM 64 installation on the remote host is affected by the following vulnerability : - A heap-based buffer overflow was discovered in bash when wide characters, not supported by the current locale set in LC_CTYPE environment variable, are printed through the echo built-in function. A local attacker, who can provide data to print through the `echo -e` built-in function, may use this flaw to crash a script or execute code with the privileges of the bash process.(CVE-2012-6711) 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 2020-06-01 modified 2020-06-02 plugin id 128945 published 2019-09-17 reporter This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/128945 title EulerOS Virtualization for ARM 64 3.0.2.0 : bash (EulerOS-SA-2019-1942) NASL family PhotonOS Local Security Checks NASL id PHOTONOS_PHSA-2019-1_0-0252_BASH.NASL description An update of the bash package has been released. last seen 2020-06-01 modified 2020-06-02 plugin id 129783 published 2019-10-11 reporter This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/129783 title Photon OS 1.0: Bash PHSA-2019-1.0-0252
References
- http://git.savannah.gnu.org/cgit/bash.git/commit/?h=devel&id=863d31ae775d56b785dc5b0105b6d251515d81d5
- http://git.savannah.gnu.org/cgit/bash.git/commit/?h=devel&id=863d31ae775d56b785dc5b0105b6d251515d81d5
- http://www.securityfocus.com/bid/108824
- http://www.securityfocus.com/bid/108824
- https://bugzilla.redhat.com/show_bug.cgi?id=1721071
- https://bugzilla.redhat.com/show_bug.cgi?id=1721071
- https://support.f5.com/csp/article/K05122252
- https://support.f5.com/csp/article/K05122252
- https://support.f5.com/csp/article/K05122252?utm_source=f5support&%3Butm_medium=RSS
- https://support.f5.com/csp/article/K05122252?utm_source=f5support&%3Butm_medium=RSS
- https://usn.ubuntu.com/4180-1/
- https://usn.ubuntu.com/4180-1/