Double Free in dropbear (Alpine package)

1) Double Free

EUVDB-ID: #VU14820

Risk: Low

CVSSv4.0: 5.9 [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/E:U/U:Clear]

CVE-ID: CVE-2017-9078

CWE-ID: CWE-415 - Double Free

Exploit availability: No

Description

The 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.

Mitigation

Install update from vendor's website.

Vulnerable software versions

dropbear (Alpine package): 2013.58-r0 - 2016.74-r0

CPE2.3

• cpe:2.3:o:alpine:dropbear_alpine_package:2013.58-r0:*:*:*:*:alpine_linux:*:2.6
• cpe:2.3:o:alpine:dropbear_alpine_package:2014.66-r0:*:*:*:*:alpine_linux:*:3.1
• cpe:2.3:o:alpine:dropbear_alpine_package:2015.67-r0:*:*:*:*:alpine_linux:*:3.1

External links

https://git.alpinelinux.org/aports/commit/?id=ea5e2a6272e38458c8d64e5cb59cfc089a5c9a93
https://git.alpinelinux.org/aports/commit/?id=9ee60284bf43844b66bb000070cc8cff672140a1
https://git.alpinelinux.org/aports/commit/?id=b204c902de27dc4e5e9efddb3dd9af012c70e268
https://git.alpinelinux.org/aports/commit/?id=b798fc52c6aa85782652617ee817f26a9412f861

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.