Double free in Dropbear
| Risk | Low |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2017-9078 CVE-2017-9079 |
| CWE-ID | CWE-415 CWE-200 |
| Exploitation vector | Local |
| Public exploit | N/A |
| Vulnerable software Subscribe |
Dropbear Server applications / Remote management servers, RDP, SSH |
| Vendor | Matt Johnston |
Security Bulletin
This security bulletin contains information about 2 vulnerabilities.
1) Double Free
EUVDB-ID: #VU14820
Risk: Low
CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2017-9078
CWE-ID:
CWE-415 - Double Free
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a double free in cleanup of TCP listeners when the -a option is enabled. The vulnerability allows a remote authenticated attacker to trigger double free error and execute arbitrary code on the target system with root privileges.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
MitigationInstall update from vendor's website.
Vulnerable software versionsDropbear: 2013.56 - 2016.74
External linkshttp://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2017q2/001985.html
http://www.debian.org/security/2017/dsa-3859
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.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.
The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Information disclosure
EUVDB-ID: #VU14821
Risk: Low
CVSSv3.1: 3.3 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2017-9079
CWE-ID:
CWE-200 - Information exposure
Exploit availability: No
DescriptionThe vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to the application allows usage of symlinks when configured with authorized_keys file format and a command= option. A local user can read certain files on the system with root privileges.
MitigationInstall updates from vendor's website.
Vulnerable software versionsDropbear: 0.28 - 2016.74
External linkshttp://matt.ucc.asn.au/dropbear/dropbear.html
http://matt.ucc.asn.au/dropbear/CHANGES
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.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.
The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
