#VU33722 Input validation error in Roundcube - CVE-2019-10740

Vulnerability identifier: #VU33722

Vulnerability risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-10740

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Roundcube
Web applications / Webmail solutions

Vendor: Roundcube

Description

The vulnerability allows a remote non-authenticated attacker to manipulate data.

In Roundcube Webmail before 1.3.10, an attacker in possession of S/MIME or PGP encrypted emails can wrap them as sub-parts within a crafted multipart email. The encrypted part(s) can further be hidden using HTML/CSS or ASCII newline characters. This modified multipart email can be re-sent by the attacker to the intended receiver. If the receiver replies to this (benign looking) email, they unknowingly leak the plaintext of the encrypted message part(s) back to the attacker.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Roundcube: 1.3.0 - 1.3.9

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External links
https://github.com/roundcube/roundcubemail/issues/6638
https://github.com/roundcube/roundcubemail/releases/tag/1.3.10
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TFFMSO5WKEYSGMTZPZFF4ZADUJ57PRN5/

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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.