#VU54076 Untrusted Pointer Dereference in Isync: mailbox synchronizer - CVE-2021-3578

Vulnerability identifier: #VU54076

Vulnerability risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-3578

CWE-ID: CWE-822

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Isync: mailbox synchronizer
Other software / Other software solutions

Vendor: ossi

Description

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to a boundary error in mbsync when processing unexpected APPENDUID response from a malicious server. A remote attacker who controls a mail server can send a specially crafted response to the client, trigger memory corruption and execute arbitrary code on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Isync: mailbox synchronizer: 1.3.0 - 1.4.1

---

External links
https://sourceforge.net/p/isync/mailman/message/37297759/
https://sourceforge.net/p/isync/isync/ci/589d2ed4283130108df5495b5510d822282e1300/

---

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.