#VU21106 Information disclosure in Mozilla Thunderbird - CVE-2019-11739

Vulnerability identifier: #VU21106

Vulnerability risk: Low

CVSSv4.0: 1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-11739

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mozilla Thunderbird
Client/Desktop applications / Messaging software

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to an error when processing multipart messages. A remote attacker can create a specially crafted multipart/alternative message that can leak encrypted S/MIME parts when included in a a HTML reply/forward.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Thunderbird: 68.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2019-30/

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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.