A vulnerability in Postfix may allow local users to gain root privileges.
| Package | Arch | Vulnerable | Unaffected |
|---|---|---|---|
| mail-mta/postfix | * | < 3.1.6 | >= 3.1.6 |
Postfix is a mail server and an alternative to the widely-used Sendmail program.
By default, Berkeley DB reads a DB_CONFIG configuration file from the current working directory. This is an undocumented behavior.
A local attacker, by using a specially crafted DG_CONFIG file, could possibly escalate privileges to the root group.
There is no known workaround at this time.
All Postfix users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-3.1.6"
A vulnerability has been found in Postfix, the worst of which possibly allowing remote code execution.
| Package | Arch | Vulnerable | Unaffected |
|---|---|---|---|
| mail-mta/postfix | * | < 2.7.4 | >= 2.7.4 |
Postfix is Wietse Venema’s mailer that attempts to be fast, easy to administer, and secure, as an alternative to the widely-used Sendmail program.
A vulnerability have been discovered in Postfix. Please review the CVE identifier referenced below for details.
An attacker could perform a man-in-the-middle attack and inject SMTP commands during the plaintext to TLS session switch or might execute arbitrary code.
There is no known workaround at this time.
All Postfix users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.7.4"
A memory leak in Postfix might allow local users to cause a Denial of Service.
| Package | Arch | Vulnerable | Unaffected |
|---|---|---|---|
| mail-mta/postfix | * | < 2.4.9, < 2.5.5 | >= 2.4.9, >= 2.5.5 |
Postfix is Wietse Venema's mailer that attempts to be fast, easy to administer, and secure, as an alternative to the widely-used Sendmail program.
It has been discovered than Postfix leaks an epoll file descriptor when executing external commands, e.g. user-controlled $HOME/.forward or $HOME/.procmailrc files. NOTE: This vulnerability only concerns Postfix instances running on Linux 2.6 kernels.
A local attacker could exploit this vulnerability to reduce the performance of Postfix, and possibly trigger an assertion, resulting in a Denial of Service.
Allow only trusted users to control delivery to non-Postfix commands.
All Postfix 2.4 users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.4.9"
All Postfix 2.5 users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.5.5"
Postfix incorrectly checks the ownership of a mailbox, allowing, in certain circumstances, to append data to arbitrary files on a local system with root privileges.
| Package | Arch | Vulnerable | Unaffected |
|---|---|---|---|
| mail-mta/postfix | * | < 2.5.3-r1 | >= 2.4.7-r1 (revision), >= 2.5.3-r1, >= 2.4.8 (revision), >= 2.4.9 |
Postfix is Wietse Venema's mailer that attempts to be fast, easy to administer, and secure, as an alternative to the widely-used Sendmail program.
Sebastian Krahmer of SuSE has found that Postfix allows to deliver mail to root-owned symlinks in an insecure manner under certain conditions. Normally, Postfix does not deliver mail to symlinks, except to root-owned symlinks, for compatibility with the systems using symlinks in /dev like Solaris. Furthermore, some systems like Linux allow to hardlink a symlink, while the POSIX.1-2001 standard requires that the symlink is followed. Depending on the write permissions and the delivery agent being used, this can lead to an arbitrary local file overwriting vulnerability (CVE-2008-2936). Furthermore, the Postfix delivery agent does not properly verify the ownership of a mailbox before delivering mail (CVE-2008-2937).
The combination of these features allows a local attacker to hardlink a root-owned symlink such that the newly created symlink would be root-owned and would point to a regular file (or another symlink) that would be written by the Postfix built-in local(8) or virtual(8) delivery agents, regardless the ownership of the final destination regular file. Depending on the write permissions of the spool mail directory, the delivery style, and the existence of a root mailbox, this could allow a local attacker to append a mail to an arbitrary file like /etc/passwd in order to gain root privileges.
The default configuration of Gentoo Linux does not permit any kind of user privilege escalation.
The second vulnerability (CVE-2008-2937) allows a local attacker, already having write permissions to the mail spool directory which is not the case on Gentoo by default, to create a previously nonexistent mailbox before Postfix creates it, allowing to read the mail of another user on the system.
The following conditions should be met in order to be vulnerable to local privilege escalation.
Consequently, each one of the following workarounds is efficient.
Concerning the second vulnerability, check the write permissions of /var/spool/mail, or check that every Unix account already has a mailbox, by using Wietse Venema's Perl script available in the official advisory.
All Postfix users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.5.3-r1"
An error in the usage of the ssl-cert eclass within multiple ebuilds might allow for disclosure of generated SSL private keys.
| Package | Arch | Vulnerable | Unaffected |
|---|---|---|---|
| app-admin/conserver | * | < 8.1.16 | >= 8.1.16 |
| mail-mta/postfix | * | < 2.4.6-r2 | >= 2.4.6-r2, >= 2.3.8-r1 (revision), >= 2.2.11-r1 (revision) |
| net-ftp/netkit-ftpd | * | < 0.17-r7 | >= 0.17-r7 |
| net-im/ejabberd | * | < 1.1.3 | >= 1.1.3 |
| net-irc/unrealircd | * | < 3.2.7-r2 | >= 3.2.7-r2 |
| net-mail/cyrus-imapd | * | < 2.3.9-r1 | >= 2.3.9-r1 |
| net-mail/dovecot | * | < 1.0.10 | >= 1.0.10 |
| net-misc/stunnel | * | < 4.21-r1 | >= 4.21-r1, < 4.0 |
| net-nntp/inn | * | < 2.4.3-r1 | >= 2.4.3-r1 |
The ssl-cert eclass is a code module used by Gentoo ebuilds to generate SSL certificates.
Robin Johnson reported that the docert() function provided by ssl-cert.eclass can be called by source building stages of an ebuild, such as src_compile() or src_install(), which will result in the generated SSL keys being included inside binary packages (binpkgs).
A local attacker could recover the SSL keys from publicly readable binary packages when "emerge" is called with the "--buildpkg (-b)" or "--buildpkgonly (-B)" option. Remote attackers can recover these keys if the packages are served to a network. Binary packages built using "quickpkg" are not affected.
Do not use pre-generated SSL keys, but use keys that were generated using a different Certificate Authority.
Upgrading to newer versions of the above packages will neither remove possibly compromised SSL certificates, nor old binary packages. Please remove the certificates installed by Portage, and then emerge an upgrade to the package.
All Conserver users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=app-admin/conserver-8.1.16"
All Postfix 2.4 users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.4.6-r2"
All Postfix 2.3 users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.3.8-r1"
All Postfix 2.2 users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.2.11-r1"
All Netkit FTP Server users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-ftp/netkit-ftpd-0.17-r7"
All ejabberd users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-im/ejabberd-1.1.3"
All UnrealIRCd users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-irc/unrealircd-3.2.7-r2"
All Cyrus IMAP Server users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-mail/cyrus-imapd-2.3.9-r1"
All Dovecot users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-mail/dovecot-1.0.10"
All stunnel 4 users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-misc/stunnel-4.21"
All InterNetNews users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-nntp/inn-2.4.3-r1"