System Security Services Daemon (SSSD) before 1.9.4, when (1) creating, (2) copying, or (3) removing a user home directory tree, allows local users to create, modify, or delete arbitrary files via a symlink attack on another user's files.

Updated sssd packages that fix one security issue and several bugs are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having low 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.

SSSD (System Security Services Daemon) provides a set of daemons to manage access to remote directories and authentication mechanisms. It provides NSS (Name Service Switch) and PAM (Pluggable Authentication Modules) interfaces toward the system and a pluggable back end system to connect to multiple different account sources.

A race condition was found in the way SSSD copied and removed user home directories. A local attacker who is able to write into the home directory of a different user who is being removed could use this flaw to perform symbolic link attacks, possibly allowing them to modify and delete arbitrary files with the privileges of the root user.
(CVE-2013-0219)

The CVE-2013-0219 issue war discovered by Florian Weimer of the Red Hat Product Security Team.

This update also fixes the following bugs :

* After a paging control was used, memory in the sssd_be process was never freed which led to the growth of the sssd_be process memory usage over time. To fix this bug, the paging control was deallocated after use, and thus the memory usage of the sssd_be process no longer grows. (BZ#820908)

* If the sssd_be process was terminated and recreated while there were authentication requests pending, the sssd_pam process did not recover correctly and did not reconnect to the new sssd_be process.
Consequently, the sssd_pam process was seemingly blocked and did not accept any new authentication requests. The sssd_pam process has been fixes so that it reconnects to the new instance of the sssd_be process after the original one terminated unexpectedly. Even after a crash and reconnect, the sssd_pam process now accepts new authentication requests. (BZ#882414)

* When the sssd_be process hung for a while, it was terminated and a new instance was created. If the old instance did not respond to the TERM signal and continued running, SSSD terminated unexpectedly. As a consequence, the user could not log in. SSSD now keeps track of sssd_be subprocesses more effectively, making the restarts of sssd_be more reliable in such scenarios. Users can now log in whenever the sssd_be is restarted and becomes unresponsive. (BZ#886165)

* In case the processing of an LDAP request took longer than the client timeout upon completing the request (60 seconds by default), the PAM client could have accessed memory that was previously freed due to the client timeout being reached. As a result, the sssd_pam process terminated unexpectedly with a segmentation fault. SSSD now ignores an LDAP request result when it detects that the set timeout of this request has been reached. The sssd_pam process no longer crashes in the aforementioned scenario. (BZ#923813)

* When there was a heavy load of users and groups to be saved in cache, SSSD experienced a timeout. Consequently, NSS did not start the backup process properly and it was impossible to log in. A patch has been provided to fix this bug. The SSSD daemon now remains responsive and the login continues as expected. (BZ#805729)

* SSSD kept the file descriptors to the log files open. Consequently, on occasions like moving the actual log file and restarting the back end, SSSD still kept the file descriptors open. SSSD now closes the file descriptor after the child process execution; after a successful back end start, the file descriptor to log files is closed.
(BZ#961680)

* While performing access control in the Identity Management back end, SSSD erroneously downloaded the 'member' attribute from the server and then attempted to use it in the cache verbatim. Consequently, the cache attempted to use the 'member' attribute values as if they were pointing to the local cache which was CPU intensive. The member attribute when processing host groups is no longer downloaded and processed. Moreover, the login process is reasonably fast even with large host groups. (BZ#979047)

All sssd users are advised to upgrade to these updated packages, which contain backported patches to correct these issues.

A race condition was found in the way SSSD copied and removed user home directories. A local attacker who is able to write into the home directory of a different user who is being removed could use this flaw to perform symbolic link attacks, possibly allowing them to modify and delete arbitrary files with the privileges of the root user.
(CVE-2013-0219)

This update also fixes the following bugs :

  - After a paging control was used, memory in the sssd_be     process was never freed which led to the growth of the     sssd_be process memory usage over time. To fix this bug,     the paging control was deallocated after use, and thus     the memory usage of the sssd_be process no longer grows.

  - If the sssd_be process was terminated and recreated     while there were authentication requests pending, the     sssd_pam process did not recover correctly and did not     reconnect to the new sssd_be process. Consequently, the     sssd_pam process was seemingly blocked and did not     accept any new authentication requests. The sssd_pam     process has been fixes so that it reconnects to the new     instance of the sssd_be process after the original one     terminated unexpectedly. Even after a crash and     reconnect, the sssd_pam process now accepts new     authentication requests.

  - When the sssd_be process hung for a while, it was     terminated and a new instance was created. If the old     instance did not respond to the TERM signal and     continued running, SSSD terminated unexpectedly. As a     consequence, the user could not log in. SSSD now keeps     track of sssd_be subprocesses more effectively, making     the restarts of sssd_be more reliable in such scenarios.
    Users can now log in whenever the sssd_be is restarted     and becomes unresponsive.

  - In case the processing of an LDAP request took longer     than the client timeout upon completing the request (60     seconds by default), the PAM client could have accessed     memory that was previously freed due to the client     timeout being reached. As a result, the sssd_pam process     terminated unexpectedly with a segmentation fault. SSSD     now ignores an LDAP request result when it detects that     the set timeout of this request has been reached. The     sssd_pam process no longer crashes in the aforementioned     scenario.

  - When there was a heavy load of users and groups to be     saved in cache, SSSD experienced a timeout.
    Consequently, NSS did not start the backup process     properly and it was impossible to log in. A patch has     been provided to fix this bug. The SSSD daemon now     remains responsive and the login continues as expected.

  - SSSD kept the file descriptors to the log files open.
    Consequently, on occasions like moving the actual log     file and restarting the back end, SSSD still kept the     file descriptors open. SSSD now closes the file     descriptor after the child process execution; after a     successful back end start, the file descriptor to log     files is closed.

  - While performing access control in the Identity     Management back end, SSSD erroneously downloaded the     'member' attribute from the server and then attempted to     use it in the cache verbatim. Consequently, the cache     attempted to use the 'member' attribute values as if     they were pointing to the local cache which was CPU     intensive. The member attribute when processing host     groups is no longer downloaded and processed. Moreover,     the login process is reasonably fast even with large     host groups.

From Red Hat Security Advisory 2013:1319 :

Updated sssd packages that fix one security issue and several bugs are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having low 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.

SSSD (System Security Services Daemon) provides a set of daemons to manage access to remote directories and authentication mechanisms. It provides NSS (Name Service Switch) and PAM (Pluggable Authentication Modules) interfaces toward the system and a pluggable back end system to connect to multiple different account sources.

A race condition was found in the way SSSD copied and removed user home directories. A local attacker who is able to write into the home directory of a different user who is being removed could use this flaw to perform symbolic link attacks, possibly allowing them to modify and delete arbitrary files with the privileges of the root user.
(CVE-2013-0219)

The CVE-2013-0219 issue war discovered by Florian Weimer of the Red Hat Product Security Team.

This update also fixes the following bugs :

* After a paging control was used, memory in the sssd_be process was never freed which led to the growth of the sssd_be process memory usage over time. To fix this bug, the paging control was deallocated after use, and thus the memory usage of the sssd_be process no longer grows. (BZ#820908)

* If the sssd_be process was terminated and recreated while there were authentication requests pending, the sssd_pam process did not recover correctly and did not reconnect to the new sssd_be process.
Consequently, the sssd_pam process was seemingly blocked and did not accept any new authentication requests. The sssd_pam process has been fixes so that it reconnects to the new instance of the sssd_be process after the original one terminated unexpectedly. Even after a crash and reconnect, the sssd_pam process now accepts new authentication requests. (BZ#882414)

* When the sssd_be process hung for a while, it was terminated and a new instance was created. If the old instance did not respond to the TERM signal and continued running, SSSD terminated unexpectedly. As a consequence, the user could not log in. SSSD now keeps track of sssd_be subprocesses more effectively, making the restarts of sssd_be more reliable in such scenarios. Users can now log in whenever the sssd_be is restarted and becomes unresponsive. (BZ#886165)

* In case the processing of an LDAP request took longer than the client timeout upon completing the request (60 seconds by default), the PAM client could have accessed memory that was previously freed due to the client timeout being reached. As a result, the sssd_pam process terminated unexpectedly with a segmentation fault. SSSD now ignores an LDAP request result when it detects that the set timeout of this request has been reached. The sssd_pam process no longer crashes in the aforementioned scenario. (BZ#923813)

* When there was a heavy load of users and groups to be saved in cache, SSSD experienced a timeout. Consequently, NSS did not start the backup process properly and it was impossible to log in. A patch has been provided to fix this bug. The SSSD daemon now remains responsive and the login continues as expected. (BZ#805729)

* SSSD kept the file descriptors to the log files open. Consequently, on occasions like moving the actual log file and restarting the back end, SSSD still kept the file descriptors open. SSSD now closes the file descriptor after the child process execution; after a successful back end start, the file descriptor to log files is closed.
(BZ#961680)

* While performing access control in the Identity Management back end, SSSD erroneously downloaded the 'member' attribute from the server and then attempted to use it in the cache verbatim. Consequently, the cache attempted to use the 'member' attribute values as if they were pointing to the local cache which was CPU intensive. The member attribute when processing host groups is no longer downloaded and processed. Moreover, the login process is reasonably fast even with large host groups. (BZ#979047)

All sssd users are advised to upgrade to these updated packages, which contain backported patches to correct these issues.

From Red Hat Security Advisory 2013:0508 :

Updated sssd packages that fix two security issues, multiple bugs, and add various enhancements are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having low 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.

The System Security Services Daemon (SSSD) provides a set of daemons to manage access to remote directories and authentication mechanisms.
It provides an NSS and PAM interface toward the system and a pluggable back-end system to connect to multiple different account sources. It is also the basis to provide client auditing and policy services for projects such as FreeIPA.

A race condition was found in the way SSSD copied and removed user home directories. A local attacker who is able to write into the home directory of a different user who is being removed could use this flaw to perform symbolic link attacks, possibly allowing them to modify and delete arbitrary files with the privileges of the root user.
(CVE-2013-0219)

Multiple out-of-bounds memory read flaws were found in the way the autofs and SSH service responders parsed certain SSSD packets. An attacker could spend a specially crafted packet that, when processed by the autofs or SSH service responders, would cause SSSD to crash.
This issue only caused a temporary denial of service, as SSSD was automatically restarted by the monitor process after the crash.
(CVE-2013-0220)

The CVE-2013-0219 and CVE-2013-0220 issues were discovered by Florian Weimer of the Red Hat Product Security Team.

These updated sssd packages also include numerous bug fixes and enhancements. Space precludes documenting all of these changes in this advisory. Users are directed to the Red Hat Enterprise Linux 6.4 Technical Notes, linked to in the References, for information on the most significant of these changes.

All SSSD users are advised to upgrade to these updated packages, which upgrade SSSD to upstream version 1.9 to correct these issues, fix these bugs and add these enhancements.

Updated sssd packages that fix two security issues, multiple bugs, and add various enhancements are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having low 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.

The System Security Services Daemon (SSSD) provides a set of daemons to manage access to remote directories and authentication mechanisms.
It provides an NSS and PAM interface toward the system and a pluggable back-end system to connect to multiple different account sources. It is also the basis to provide client auditing and policy services for projects such as FreeIPA.

A race condition was found in the way SSSD copied and removed user home directories. A local attacker who is able to write into the home directory of a different user who is being removed could use this flaw to perform symbolic link attacks, possibly allowing them to modify and delete arbitrary files with the privileges of the root user.
(CVE-2013-0219)

Multiple out-of-bounds memory read flaws were found in the way the autofs and SSH service responders parsed certain SSSD packets. An attacker could spend a specially crafted packet that, when processed by the autofs or SSH service responders, would cause SSSD to crash.
This issue only caused a temporary denial of service, as SSSD was automatically restarted by the monitor process after the crash.
(CVE-2013-0220)

The CVE-2013-0219 and CVE-2013-0220 issues were discovered by Florian Weimer of the Red Hat Product Security Team.

These updated sssd packages also include numerous bug fixes and enhancements. Space precludes documenting all of these changes in this advisory. Users are directed to the Red Hat Enterprise Linux 6.4 Technical Notes, linked to in the References, for information on the most significant of these changes.

All SSSD users are advised to upgrade to these updated packages, which upgrade SSSD to upstream version 1.9 to correct these issues, fix these bugs and add these enhancements.

A race condition was found in the way SSSD copied and removed user home directories. A local attacker who is able to write into the home directory of a different user who is being removed could use this flaw to perform symbolic link attacks, possibly allowing them to modify and delete arbitrary files with the privileges of the root user.
(CVE-2013-0219)

Multiple out-of-bounds memory read flaws were found in the way the autofs and SSH service responders parsed certain SSSD packets. An attacker could spend a specially crafted packet that, when processed by the autofs or SSH service responders, would cause SSSD to crash.
This issue only caused a temporary denial of service, as SSSD was automatically restarted by the monitor process after the crash.
(CVE-2013-0220)

A rebase to the latest LTM upstream relase that fixes CVE-2013-0220 and CVE-2013-0219

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.

A rebase to the latest LTM upstream relase that fixes CVE-2013-0220 and CVE-2013-0219.

Also fixes recreating the Kerberos cache when any part of the ccache directory is gone.

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
79151	CentOS 5 : sssd (CESA-2013:1319)	Nessus	CentOS Local Security Checks	low
70391	Scientific Linux Security Update : sssd on SL5.x i386/x86_64 (20130930)	Nessus	Scientific Linux Local Security Checks	low
70347	Oracle Linux 5 : sssd (ELSA-2013-1319)	Nessus	Oracle Linux Local Security Checks	low
70246	RHEL 5 : sssd (RHSA-2013:1319)	Nessus	Red Hat Local Security Checks	low
68747	Oracle Linux 6 : sssd (ELSA-2013-0508)	Nessus	Oracle Linux Local Security Checks	medium
65142	CentOS 6 : sssd (CESA-2013:0508)	Nessus	CentOS Local Security Checks	medium
65016	Scientific Linux Security Update : sssd on SL6.x i386/x86_64 (20130221)	Nessus	Scientific Linux Local Security Checks	medium
64758	RHEL 6 : sssd (RHSA-2013:0508)	Nessus	Red Hat Local Security Checks	medium
64602	Fedora 17 : sssd-1.8.6-1.fc17 (2013-1826)	Nessus	Fedora Local Security Checks	medium
64545	Fedora 18 : sssd-1.9.4-2.fc18 (2013-1795)	Nessus	Fedora Local Security Checks	medium

Detections

Analytics

CVE-2013-0219

medium

Tenable Plugins

low

low

low

low

medium

medium

medium

medium

medium

medium