Vulnerability identifier: #VU33333

Vulnerability risk: Low

CVSSv3.1: 4.5 [CVSS:3.1/CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2011-1678

CWE-ID: CWE-20

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Samba
Server applications / Directory software, identity management

Vendor: Samba

Description

The vulnerability allows a local non-authenticated attacker to read and manipulate data.

smbfs in Samba 3.5.8 and earlier attempts to use (1) mount.cifs to append to the /etc/mtab file and (2) umount.cifs to append to the /etc/mtab.tmp file without first checking whether resource limits would interfere, which allows local users to trigger corruption of the /etc/mtab file via a process with a small RLIMIT_FSIZE value, a related issue to CVE-2011-1089.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Samba: 3.5.0 - 3.5.8

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External links
http://openwall.com/lists/oss-security/2011/03/04/10
http://openwall.com/lists/oss-security/2011/03/04/11
http://openwall.com/lists/oss-security/2011/03/04/12
http://openwall.com/lists/oss-security/2011/03/04/9
http://openwall.com/lists/oss-security/2011/03/05/3
http://openwall.com/lists/oss-security/2011/03/05/7
http://openwall.com/lists/oss-security/2011/03/07/9
http://openwall.com/lists/oss-security/2011/03/14/16
http://openwall.com/lists/oss-security/2011/03/14/5
http://openwall.com/lists/oss-security/2011/03/14/7
http://openwall.com/lists/oss-security/2011/03/15/6
http://openwall.com/lists/oss-security/2011/03/22/4
http://openwall.com/lists/oss-security/2011/03/22/6
http://openwall.com/lists/oss-security/2011/03/31/3
http://openwall.com/lists/oss-security/2011/03/31/4
http://openwall.com/lists/oss-security/2011/04/01/2
http://www.mandriva.com/security/advisories?name=MDVSA-2011:148
http://bugzilla.redhat.com/show_bug.cgi?id=688980
http://exchange.xforce.ibmcloud.com/vulnerabilities/66702

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.