Bug 1813930 (CVE-2020-5202)

Summary: CVE-2020-5202 apt-cacher-ng: local unprivileged user can impersonate the apt-cacher-ng daemon leading to credentials leak
Product: [Other] Security Response Reporter: Guilherme de Almeida Suckevicz <gsuckevi>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED UPSTREAM QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: extras-orphan, knakayam
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Last Closed: 2020-03-16 16:31:43 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 1813931, 1813932    
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Description Guilherme de Almeida Suckevicz 2020-03-16 14:10:30 UTC 
apt-cacher-ng through 3.3 allows local users to obtain sensitive information by hijacking the hardcoded TCP port. The /usr/lib/apt-cacher-ng/acngtool program attempts to connect to apt-cacher-ng via TCP on localhost port 3142, even if the explicit SocketPath=/var/run/apt-cacher-ng/socket command-line option is passed. The cron job /etc/cron.daily/apt-cacher-ng (which is active by default) attempts this periodically. Because 3142 is an unprivileged port, any local user can try to bind to this port and will receive requests from acngtool. There can be sensitive data in these requests, e.g., if AdminAuth is enabled in /etc/apt-cacher-ng/security.conf. This sensitive data can leak to unprivileged local users that manage to bind to this port before the apt-cacher-ng daemon can.

References:
http://www.openwall.com/lists/oss-security/2020/01/20/4
https://seclists.org/oss-sec/2020/q1/21
Comment 1 Guilherme de Almeida Suckevicz 2020-03-16 14:11:44 UTC 
Created apt-cacher-ng tracking bugs for this issue:

Affects: epel-7 [bug 1813932]
Affects: fedora-all [bug 1813931]
Comment 2 Product Security DevOps Team 2020-03-16 16:31:43 UTC 
This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.