Amazon Linux 2 : pcs (ALAS-2018-1005)
Medium Nessus Plugin ID 109365
SynopsisThe remote Amazon Linux 2 host is missing a security update.
DescriptionDebug parameter removal bypass, allowing information disclosure
It was found that the REST interface of the pcsd service did not properly remove the pcs debug argument from the /run_pcs query, possibly disclosing sensitive information. A remote attacker with a valid token could use this flaw to elevate their privilege.
Timing attack in authenticity_token.rb
Sinatra rack-protection versions 1.5.4 and 2.0.0.rc3 and earlier contains a timing attack vulnerability in the CSRF token checking that can result in signatures can be exposed. This attack appear to be exploitable via network connectivity to the ruby application. This vulnerability appears to have been fixed in 1.5.5 and 2.0.0.
Privilege escalation via authorized user malicious REST call
It was found that the REST interface of the pcsd service did not properly sanitize the file name from the /remote/put_file query. If the /etc/booth directory exists, an authenticated attacker with write permissions could create or overwrite arbitrary files with arbitrary data outside of the /etc/booth directory, in the context of the pcsd process. (CVE-2018-1079)
SolutionRun 'yum update pcs' to update your system.