Deserialization of Untrusted Data in PHPMailer

1) Deserialization of Untrusted Data

EUVDB-ID: #VU52850

Risk: High

CVSSv3.1: 7.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-36326

CWE-ID: CWE-502 - Deserialization of Untrusted Data

Exploit availability: No

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to insecure input validation when processing serialized data in "addAttachment". A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

PHPMailer: 6.1.8 - 6.4.0

External links

http://github.com/PHPMailer/PHPMailer/commit/e2e07a355ee8ff36aba21d0242c5950c56e4c6f9
http://github.com/PHPMailer/PHPMailer/commit/26f2848d3bbb57add5f34a467a1e3b2f9ce5cd2a

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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