Bugzilla – Bug 958582
VUL-0: CVE-2015-5252: samba: Insufficient symlink verification (file access outside the share)
Last modified: 2016-04-20 10:12:12 UTC
3.x patches were not yet attached
QA REPRODUCER: problem seems to be in share definitions /share /share1 giving access to /share without leading / will also give access to /share1 (see description). perhaps the samba team can improve on this reproduction description.
An update workflow for this issue was started. This issue was rated as "important". Please submit fixed packages until "Dec. 17, 2015". When done, reassign the bug to "security-team@suse.de". /update/121110/.
An update workflow for this issue was started. This issue was rated as moderate. Please submit fixed packages until 2015-12-24. When done, reassign the bug to security-team@suse.de. https://swamp.suse.de/webswamp/wf/62372
An update workflow for this issue was started. This issue was rated as "important". Please submit fixed packages until "Dec. 17, 2015". When done, reassign the bug to "security-team@suse.de". /update/62372/.
bugbot adjusting priority
is public now https://www.samba.org/samba/security/CVE-2015-5252.html =========================================================== == Subject: Insufficient symlink verification in smbd. == == CVE ID#: CVE-2015-5252 == == Versions: All versions of Samba, from 3.0.0 to 4.3.2 == == Summary: Insufficient symlink verification could allow == data access outside share path. == =========================================================== =========== Description =========== All versions of Samba from 3.0.0 to 4.3.2 inclusive are vulnerable to a bug in symlink verification, which under certain circumstances could allow client access to files outside the exported share path. If a Samba share is configured with a path that shares a common path prefix with another directory on the file system, the smbd daemon may allow the client to follow a symlink pointing to a file or directory in that other directory, even if the share parameter "wide links" is set to "no" (the default). For example. Given two directories on the file system: /share/ /share1/ If a Samba share is created as follows: [sharename] path = /share wide links = no Then a symlink with the path /share/symlink -> /share1/file would be followed by smbd, due to the fact that only the string "/share" is checked to see if it matches the target path. This means a path that starts with "/share", such as "/share1" will also match. ================== Patch Availability ================== Patches addressing this defect have been posted to https://www.samba.org/samba/history/security.html Additionally, Samba 4.3.3, 4.2.7 and 4.1.22 have been issued as security releases to correct the defect. Samba vendors and administrators running affected versions are advised to upgrade or apply the patch as soon as possible. =========== Workarounds =========== Ensure all exported share paths do not share base path names with other directories on the file system. Please note, setting the smb.conf variable "follow symlinks = no" is *NOT* a workaround for this problem, as this only prohibits smbd from following a symlink at the end of a path. A symlink could be created that points to the directory which shares a base path name instead, and smbd would still follow that link. For example, with the above share definition, given a symlink of: /share/symlink -> /share1 a client could send a relative path such as "symlink/file", which would still be followed by smbd as the end component "file" of "symlink/file" is *NOT* a symlink, and so is not affected by "follow symlinks = no". ======= Credits ======= The problem was found by Jan "Yenya" Kasprzak and the Computer Systems Unit team at Faculty of Informatics, Masaryk University. The fix was created by Jeremy Allison of Google.
This is an autogenerated message for OBS integration: This bug (958582) was mentioned in https://build.opensuse.org/request/show/349211 Factory / samba
SUSE-SU-2015:2304-1: An update that solves 6 vulnerabilities and has 17 fixes is now available. Category: security (important) Bug References: 295284,773464,872912,901813,902421,910378,912457,913304,923374,931854,936909,939051,947552,949022,951660,953382,954658,958581,958582,958583,958584,958585,958586 CVE References: CVE-2015-3223,CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330,CVE-2015-8467 Sources used: SUSE Linux Enterprise Software Development Kit 12 (src): ldb-1.1.24-4.3.1, samba-4.1.12-18.3.1, talloc-2.1.5-3.4.1, tdb-1.3.8-2.3.1, tevent-0.9.26-3.3.1 SUSE Linux Enterprise Server 12 (src): ldb-1.1.24-4.3.1, samba-4.1.12-18.3.1, talloc-2.1.5-3.4.1, tdb-1.3.8-2.3.1, tevent-0.9.26-3.3.1 SUSE Linux Enterprise Desktop 12 (src): ldb-1.1.24-4.3.1, samba-4.1.12-18.3.1, talloc-2.1.5-3.4.1, tdb-1.3.8-2.3.1, tevent-0.9.26-3.3.1
SUSE-SU-2015:2305-1: An update that solves 6 vulnerabilities and has three fixes is now available. Category: security (important) Bug References: 949022,951660,954658,958581,958582,958583,958584,958585,958586 CVE References: CVE-2015-3223,CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330,CVE-2015-8467 Sources used: SUSE Linux Enterprise Software Development Kit 12-SP1 (src): ldb-1.1.24-4.1, samba-4.2.4-6.1, talloc-2.1.5-4.1, tdb-1.3.8-4.1, tevent-0.9.26-4.1 SUSE Linux Enterprise Server 12-SP1 (src): ldb-1.1.24-4.1, samba-4.2.4-6.1, talloc-2.1.5-4.1, tdb-1.3.8-4.1, tevent-0.9.26-4.1 SUSE Linux Enterprise Desktop 12-SP1 (src): ldb-1.1.24-4.1, samba-4.2.4-6.1, talloc-2.1.5-4.1, tdb-1.3.8-4.1, tevent-0.9.26-4.1
Submitted for SLE10SP3 (both gplv3 and gplv2 versions). It complained but submitted to SLE11SP1. And it refused to submit in SLES9 for Teradata. packages for the SLE9 and SLE11SP1 can be found in home:lmuelle:branches:OBS_Maintained:samba
openSUSE-SU-2015:2354-1: An update that solves 6 vulnerabilities and has three fixes is now available. Category: security (important) Bug References: 949022,951660,954658,958581,958582,958583,958584,958585,958586 CVE References: CVE-2015-3223,CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330,CVE-2015-8467 Sources used: openSUSE Leap 42.1 (src): ldb-1.1.24-7.1, samba-4.2.4-9.2, talloc-2.1.5-7.1, tdb-1.3.8-7.1, tevent-0.9.26-7.1
openSUSE-SU-2015:2356-1: An update that solves 7 vulnerabilities and has 6 fixes is now available. Category: security (important) Bug References: 939050,939051,949022,951660,953382,954658,958580,958581,958582,958583,958584,958585,958586 CVE References: CVE-2015-3223,CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330,CVE-2015-7540,CVE-2015-8467 Sources used: openSUSE 13.2 (src): ldb-1.1.24-3.4.1, samba-4.1.22-21.1, talloc-2.1.5-2.6.1, tdb-1.3.8-3.1, tevent-0.9.26-3.1 openSUSE 13.1 (src): ldb-1.1.24-3.7.1, samba-4.1.22-3.46.1, talloc-2.1.5-7.10.1, tdb-1.3.8-4.7.1, tevent-0.9.26-4.7.1
SUSE-SU-2016:0032-1: An update that solves four vulnerabilities and has 8 fixes is now available. Category: security (important) Bug References: 295284,773464,901813,912457,913304,934299,948244,949022,958582,958583,958584,958586 CVE References: CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330 Sources used: SUSE Linux Enterprise Server 11-SP2-LTSS (src): samba-3.6.3-45.2, samba-doc-3.6.3-45.2 SUSE Linux Enterprise Debuginfo 11-SP2 (src): samba-3.6.3-45.2
done
SUSE-SU-2016:0164-1: An update that solves four vulnerabilities and has 7 fixes is now available. Category: security (important) Bug References: 295284,912457,934299,936909,948244,949022,953382,958582,958583,958584,958586 CVE References: CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330 Sources used: SUSE Linux Enterprise Software Development Kit 11-SP4 (src): samba-3.6.3-64.1 SUSE Linux Enterprise Software Development Kit 11-SP3 (src): samba-3.6.3-64.1 SUSE Linux Enterprise Server for VMWare 11-SP3 (src): samba-3.6.3-64.1, samba-doc-3.6.3-64.1 SUSE Linux Enterprise Server 11-SP4 (src): samba-3.6.3-64.1, samba-doc-3.6.3-64.1 SUSE Linux Enterprise Server 11-SP3 (src): samba-3.6.3-64.1, samba-doc-3.6.3-64.1 SUSE Linux Enterprise Desktop 11-SP4 (src): samba-3.6.3-64.1, samba-doc-3.6.3-64.1 SUSE Linux Enterprise Desktop 11-SP3 (src): samba-3.6.3-64.1, samba-doc-3.6.3-64.1 SUSE Linux Enterprise Debuginfo 11-SP4 (src): samba-3.6.3-64.1 SUSE Linux Enterprise Debuginfo 11-SP3 (src): samba-3.6.3-64.1
An update workflow for this issue was started. This issue was rated as important. Please submit fixed packages until 2016-04-22. When done, reassign the bug to security-team@suse.de. https://swamp.suse.de/webswamp/wf/62632
openSUSE-SU-2016:1064-1: An update that solves 16 vulnerabilities and has 17 fixes is now available. Category: security (important) Bug References: 898031,901813,912457,913238,913547,914279,917376,919309,924519,936862,942716,946051,947552,949022,958581,958582,958583,958584,958585,958586,964023,966271,968222,968973,971965,972197,973031,973032,973033,973034,973036,973832,974629 CVE References: CVE-2014-8143,CVE-2015-0240,CVE-2015-3223,CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330,CVE-2015-5370,CVE-2015-7560,CVE-2015-8467,CVE-2016-2110,CVE-2016-2111,CVE-2016-2112,CVE-2016-2113,CVE-2016-2115,CVE-2016-2118 Sources used: openSUSE 13.2 (src): samba-4.2.4-34.1
SUSE-SU-2016:1105-1: An update that solves three vulnerabilities and has one errata is now available. Category: security (important) Bug References: 913087,958582,973031,973032 CVE References: CVE-2015-5252,CVE-2016-2110,CVE-2016-2111 Sources used: SUSE Linux Enterprise Server 10 SP4 LTSS (src): samba-3.0.36-0.13.32.1, samba-doc-3.0.36-0.12.32.1
openSUSE-SU-2016:1106-1: An update that fixes 17 vulnerabilities is now available. Category: security (important) Bug References: 844720,849224,853347,917376,936862,958582,958583,958584,958586,968222,971965,973031,973032,973033,973034,973035,973036 CVE References: CVE-2012-6150,CVE-2013-4408,CVE-2013-4496,CVE-2015-0240,CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330,CVE-2015-5370,CVE-2015-7560,CVE-2016-2110,CVE-2016-2111,CVE-2016-2112,CVE-2016-2113,CVE-2016-2114,CVE-2016-2115,CVE-2016-2118 Sources used: openSUSE 13.1 (src): samba-4.2.4-3.54.2
openSUSE-SU-2016:1107-1: An update that fixes 17 vulnerabilities is now available. Category: security (important) Bug References: 844720,849224,853347,917376,936862,958582,958583,958584,958586,968222,971965,973031,973032,973033,973034,973035,973036 CVE References: CVE-2012-6150,CVE-2013-4408,CVE-2013-4496,CVE-2015-0240,CVE-2015-5252,CVE-2015-5296,CVE-2015-5299,CVE-2015-5330,CVE-2015-5370,CVE-2015-7560,CVE-2016-2110,CVE-2016-2111,CVE-2016-2112,CVE-2016-2113,CVE-2016-2114,CVE-2016-2115,CVE-2016-2118 Sources used: openSUSE Evergreen 11.4 (src): samba-3.6.3-141.1, samba-doc-3.6.3-141.1