SystemTap 1.4, when unprivileged (aka stapusr) mode is enabled, allows local users to cause a denial of service (divide-by-zero error and OOPS) via a crafted ELF program with DWARF expressions that are not properly handled by a stap script that performs stack unwinding (aka backtracing).

The remote Oracle Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2011-0842 advisory.

    [1.4.6.0.1.el6_1.1]
    - remove doc/SystemTap_Beginners_Guide/en-US in tarball
    - comment bz683569.patch in specfile

    [1.3-4.1]
    - bz702687 (patch)

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

From Red Hat Security Advisory 2011:0841 :

Updated systemtap packages that fix one security issue are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.

SystemTap is an instrumentation system for systems running the Linux kernel, version 2.6. Developers can write scripts to collect data on the operation of the system.

A divide-by-zero flaw was found in the way SystemTap handled malformed debugging information in DWARF format. When SystemTap unprivileged mode was enabled, an unprivileged user in the stapusr group could use this flaw to crash the system. Additionally, a privileged user (root, or a member of the stapdev group) could trigger this flaw when tricked into instrumenting a specially crafted ELF binary, even when unprivileged mode was not enabled. (CVE-2011-1769)

SystemTap users should upgrade to these updated packages, which contain a backported patch to correct this issue.

Updated systemtap packages that fix one security issue are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.

SystemTap is an instrumentation system for systems running the Linux kernel, version 2.6. Developers can write scripts to collect data on the operation of the system.

A divide-by-zero flaw was found in the way SystemTap handled malformed debugging information in DWARF format. When SystemTap unprivileged mode was enabled, an unprivileged user in the stapusr group could use this flaw to crash the system. Additionally, a privileged user (root, or a member of the stapdev group) could trigger this flaw when tricked into instrumenting a specially crafted ELF binary, even when unprivileged mode was not enabled. (CVE-2011-1769)

SystemTap users should upgrade to these updated packages, which contain a backported patch to correct this issue.

Multiple vulnerabilities has been discovered and corrected in systemtap :

SystemTap 1.4 and earlier, when unprivileged (aka stapusr) mode is enabled, allows local users to cause a denial of service (divide-by-zero error and OOPS) via a crafted ELF program with DWARF expressions that are not properly handled by a stap script that performs context variable access (CVE-2011-1769).

SystemTap 1.4, when unprivileged (aka stapusr) mode is enabled, allows local users to cause a denial of service (divide-by-zero error and OOPS) via a crafted ELF program with DWARF expressions that are not properly handled by a stap script that performs stack unwinding (aka backtracing) (CVE-2011-1781).

The updated packages have been patched to correct these issues.

SystemTap is an instrumentation system for systems running the Linux kernel, version 2.6. Developers can write scripts to collect data on the operation of the system.

Two divide-by-zero flaws were found in the way SystemTap handled malformed debugging information in DWARF format. When SystemTap unprivileged mode was enabled, an unprivileged user in the stapusr group could use these flaws to crash the system. Additionally, a privileged user (root, or a member of the stapdev group) could trigger these flaws when tricked into instrumenting a specially crafted ELF binary, even when unprivileged mode was not enabled. (CVE-2011-1769, CVE-2011-1781)

SystemTap users should upgrade to these updated packages, which contain a backported patch to correct these issues.

Updated systemtap packages that fix two security issues are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

SystemTap is an instrumentation system for systems running the Linux kernel, version 2.6. Developers can write scripts to collect data on the operation of the system.

Two divide-by-zero flaws were found in the way SystemTap handled malformed debugging information in DWARF format. When SystemTap unprivileged mode was enabled, an unprivileged user in the stapusr group could use these flaws to crash the system. Additionally, a privileged user (root, or a member of the stapdev group) could trigger these flaws when tricked into instrumenting a specially crafted ELF binary, even when unprivileged mode was not enabled. (CVE-2011-1769, CVE-2011-1781)

SystemTap users should upgrade to these updated packages, which contain a backported patch to correct these issues.

Two divide-by-zero flaws were found in the way systemtap interpreted certain corrupted DWARF expressions. A privileged user able to execute arbitrary systemtap scripts could be tricked into triggering this flaw to crash the target machine. An unprivileged user (in the stapusr group) may be able to trigger this flaw to crash the target machine, only if unprivileged mode was enabled by the system administrator.

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.

ID	Name	Product	Family	Severity
68282	Oracle Linux 6 : systemtap (ELSA-2011-0842)	Nessus	Oracle Linux Local Security Checks	medium
68281	Oracle Linux 5 : systemtap (ELSA-2011-0841)	Nessus	Oracle Linux Local Security Checks	low
67083	CentOS 5 : systemtap (CESA-2011:0841)	Nessus	CentOS Local Security Checks	low
61932	Mandriva Linux Security Advisory : systemtap (MDVSA-2011:155)	Nessus	Mandriva Local Security Checks	low
61062	Scientific Linux Security Update : systemtap on SL6.x i386/x86_64	Nessus	Scientific Linux Local Security Checks	low
54930	RHEL 6 : systemtap (RHSA-2011:0842)	Nessus	Red Hat Local Security Checks	low
54837	Fedora 15 : systemtap-1.4-9.fc15 (2011-7314)	Nessus	Fedora Local Security Checks	low
54836	Fedora 14 : systemtap-1.4-6.fc14 (2011-7302)	Nessus	Fedora Local Security Checks	high
54835	Fedora 13 : systemtap-1.4-6.fc13 (2011-7289)	Nessus	Fedora Local Security Checks	high

Detections

Analytics

CVE-2011-1781

medium

Tenable Plugins

medium

low

low

low

low

low

low

high

high