#VU35855 Information disclosure in pam-u2f - CVE-2019-12209
Published: June 4, 2019 / Updated: August 8, 2020
Vulnerability identifier: #VU35855
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2019-12209
CWE-ID: CWE-200
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
pam-u2f
pam-u2f
Software vendor:
Yubico
Yubico
Description
The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.
Yubico pam-u2f 1.0.7 attempts parsing of the configured authfile (default $HOME/.config/Yubico/u2f_keys) as root (unless openasuser was enabled), and does not properly verify that the path lacks symlinks pointing to other files on the system owned by root. If the debug option is enabled in the PAM configuration, part of the file contents of a symlink target will be logged, possibly revealing sensitive information.
Remediation
Install update from vendor's website.
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
- https://developers.yubico.com/pam-u2f/Release_Notes.html
- https://github.com/Yubico/pam-u2f/commit/7db3386fcdb454e33a3ea30dcfb8e8960d4c3aa3
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5FOR4ADC356JPCHAJI5UXZORLC3VNBPS/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZCGU6UQLI3ZTW3UYCTMQW7VDL5M4LCWR/