Remote code execution in libarchive

1) Use-after-free

EUVDB-ID: #VU22332

Risk: High

CVSSv3.1: 8.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-18408

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error within the archive_read_format_rar_read_data() function in archive_read_support_format_rar.c in libarchive when handling certain ARCHIVE_FAILED situation, related to Ppmd7_DecodeSymbol. A remote attacker can create a specially crafted archive, pass it to the affected application trigger a use-after-free error and crash the application or execute arbitrary code on the target system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

libarchive: 2.6.0 - 3.3.3

External links

http://bugs.chromium.org/p/oss-fuzz/issues/detail?id=14689
http://github.com/libarchive/libarchive/commit/b8592ecba2f9e451e1f5cb7ab6dcee8b8e7b3f60
http://github.com/libarchive/libarchive/compare/v3.3.3...v3.4.0

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to open a a specially crafted archive.

Is there known malware, which exploits this vulnerability?

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