Vulnerability Note VU#338343
strongSwan VPN charon server vulnerable to buffer underflow
strongSwan VPN's charon server prior to version 5.6.3 does not check packet length and may allow buffer underflow, resulting in denial of service.
CWE-124: Buffer Underwrite ('Buffer Underflow') - CVE-2018-5388
In stroke_socket.c, a missing packet length check could allow a buffer underflow, which may lead to resource exhaustion and denial of service while reading from the socket.
According to the vendor, an attacker must typically have local root permissions to access the socket. However, other accounts and groups such as the vpn group (if capability dropping in enabled, for example) may also have sufficient permissions, but this configuration does not appear to be the default behavior.
A remote attacker with local user credentials (possibly a normal user in the vpn group, or root) may be able to underflow the buffer and cause a denial of service.
Apply an update
StrongSwan version 5.6.3 and above contain a patch for this issue.
Vendor Information (Learn More)
If you are a vendor and your product is affected, let
us know.View More »
|Vendor||Status||Date Notified||Date Updated|
|strongSwan||Affected||21 Mar 2018||24 May 2018|
|SUSE Linux||Affected||23 May 2018||24 May 2018|
|Alpine Linux||Unknown||23 May 2018||23 May 2018|
|Arch Linux||Unknown||23 May 2018||23 May 2018|
|Arista Networks, Inc.||Unknown||23 May 2018||23 May 2018|
|ASP Linux||Unknown||23 May 2018||23 May 2018|
|CentOS||Unknown||23 May 2018||23 May 2018|
|CoreOS||Unknown||23 May 2018||23 May 2018|
|Debian GNU/Linux||Unknown||23 May 2018||23 May 2018|
|ENEA||Unknown||23 May 2018||23 May 2018|
|Fedora Project||Unknown||23 May 2018||23 May 2018|
|Geexbox||Unknown||23 May 2018||23 May 2018|
|Gentoo Linux||Unknown||23 May 2018||23 May 2018|
|HomeSeer||Unknown||23 May 2018||23 May 2018|
|Micro Focus||Unknown||23 May 2018||23 May 2018|
Thanks to Kevin Backhouse of Semmle Ltd. for reporting this vulnerability.
This document was written by Garret Wassermann.
22 May 2018
Date First Published:
23 May 2018
Date Last Updated:
13 Jun 2018
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