GLSA 200312-03: rsync: exploitable heap overflow

Title:rsync: exploitable heap overflow


rsync contains a heap overflow vulnerability that can be used to execute arbitrary code.


rsync is a popular file transfer package used to synchronize the Portage tree.

Affected packages

Package Vulnerable Unaffected Architecture(s)
net-misc/rsync < 2.5.7 >= 2.5.7 All supported architectures


Rsync version 2.5.6 contains a vulnerability that can be used to run arbitrary code. The Gentoo infrastructure team has some reasonably good forensic evidence that this exploit may have been used in combination with the Linux kernel do_brk() vulnerability (see GLSA 200312-02) to exploit a rotation server (see GLSA-200312-01.)

Please see for the security advisory released by the rsync development team.


A remote attacker could execute arbitrary code with the permissions of the root user.


There is no known workaround at this time.


To address this vulnerability, all Gentoo users should read GLSA-200312-02 and ensure that all systems are upgraded to a version of the Linux kernel without the do_brk() vulnerability, and upgrade to version 2.5.7 of rsync:

    # emerge sync
    # emerge -pv '>=net-misc/rsync-2.5.7'
    # emerge '>=net-misc/rsync-2.5.7'
    # emerge clean

Review your /etc/rsync/rsyncd.conf configuration file; ensure that the use chroot="no" command is commented out or removed, or change use chroot="no" to use chroot="yes". Then, if necessary, restart rsyncd:

# /etc/init.d/rsyncd restart



This GLSA and any updates to it are available for viewing at the Gentoo Security Website:


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