UNIX symbolic link following in storeBackup - CVE-2020-7040
Published: January 29, 2020 / Updated: May 4, 2021
Vulnerability identifier: #VU24715
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2020-7040
CWE-ID: CWE-61
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a symlink following issue within the storeBackup.pl in storeBackup, as software relies on the /tmp/storeBackup.lock pathname. A local user can create a specially crafted symbolic link to a critical file on the system and overwrite it with privileges of the application.
Successful exploitation of this vulnerability may result in privilege escalation.
Affected software
storeBackup
SUSE Linux
Opensuse
Ubuntu
storebackup (Ubuntu package)
SUSE Linux
Opensuse
Ubuntu
storebackup (Ubuntu package)
How to mitigate CVE-2020-7040
Install update from vendor's website.
storeBackup - update to 3.5.1
storebackup (Ubuntu package) - addressed in versions 3.2.1-1+deb8u1build0.16.04.1, 3.2.1-1+deb8u1build0.18.04.1, 3.2.1-1+deb8u1build0.20.04.1
storebackup (Ubuntu package) - addressed in versions 3.2.1-1+deb8u1build0.16.04.1, 3.2.1-1+deb8u1build0.18.04.1, 3.2.1-1+deb8u1build0.20.04.1
External References
- http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00054.html
- http://www.openwall.com/lists/oss-security/2020/01/20/3
- http://www.openwall.com/lists/oss-security/2020/01/21/2
- http://www.openwall.com/lists/oss-security/2020/01/22/2
- http://www.openwall.com/lists/oss-security/2020/01/22/3
- http://www.openwall.com/lists/oss-security/2020/01/23/1
- https://bugzilla.suse.com/show_bug.cgi?id=CVE-2020-7040
- https://seclists.org/oss-sec/2020/q1/20