Denial of service in libarchive

1) Use-after-free

EUVDB-ID: #VU59459

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-36976

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a use-after-free error in copy_string. A remote attacker can cause a denial of service condition on the target system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

libarchive: 2.6.0 - 3.5.1

External links

http://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32375
http://github.com/google/oss-fuzz-vulns/blob/main/vulns/libarchive/OSV-2021-557.yaml

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.