Vulnerability identifier: #VU35856

Vulnerability risk: High

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-12210

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
pam-u2f
Web applications / Other software

Vendor: Yubico

Description

The vulnerability allows a remote authenticated user to read and manipulate data.

In Yubico pam-u2f 1.0.7, when configured with debug and a custom debug log file is set using debug_file, that file descriptor is not closed when a new process is spawned. This leads to the file descriptor being inherited into the child process; the child process can then read from and write to it. This can leak sensitive information and also, if written to, be used to fill the disk or plant misinformation.

Mitigation
Install update from vendor's website.

Vulnerable software versions

pam-u2f: 1.0.7

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External links
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00012.html
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00018.html
http://www.openwall.com/lists/oss-security/2019/06/05/1
http://developers.yubico.com/pam-u2f/Release_Notes.html
http://github.com/Yubico/pam-u2f/commit/18b1914e32b74ff52000f10e97067e841e5fff62

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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