It was discovered that the ghostscript /invalidaccess checks fail under certain conditions. A specially crafted PostScript document could possibly exploit this to bypass the -dSAFER protection and, for example, execute arbitrary shell commands.
External References: http://seclists.org/oss-sec/2018/q3/142
Acknowledgments: Name: Tavis Ormandy (Google Project Zero)
Mediawiki was only introduced in OCP 3.x in version 3.6. Setting 3.5 and earlier as not affected. References: https://access.redhat.com/containers/?tab=tags#/registry.access.redhat.com/openshift3/mediawiki-apb https://access.redhat.com/containers/?tab=tags#/registry.access.redhat.com/openshift3/mediawiki-123
While the openshift3/mediawiki123-123 container has the ghostscript and ImageMagick rpms installed they aren't used by anything. Setting all OCP 3.x versions to not affected.
Upstream Patches: http://git.ghostscript.com/?p=ghostpdl.git;a=commit;h=5516c614dc33 http://git.ghostscript.com/?p=ghostpdl.git;a=commit;h=78911a01b67d http://git.ghostscript.com/?p=ghostpdl.git;a=commit;h=79cccf641486 http://git.ghostscript.com/?p=ghostpdl.git;a=commit;h=520bb0ea7519
when will the fix for Red Hat Enterprise Linux 7 be released? Thanks!
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2018:2918 https://access.redhat.com/errata/RHSA-2018:2918
Would like to ask if the recent release of EXPLOIT code on the web, and the news reports of this vulnerability being exploited in the wild increases RedHat's rating. Also, according to https://access.redhat.com/support/policy/updates/errata/ RHEL6 in "Maintenance" mode has the same "Yes" in the column for Asynchronous Security Errata as it did under the prior life cycle phases. Please produce a patch for RHEL6.
Statement: This issue did affect the versions of ghostscript as shipped with Red Hat Enterprise Linux 5, 6, and 7. Red Hat Enterprise Linux 5 is now in Extended Life Phase of the support and maintenance life cycle. This issue is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
Created ghostscript tracking bugs for this issue: Affects: fedora-all [bug 1654362]
This issue has been addressed in the following products: Red Hat Enterprise Linux 6 Via RHSA-2018:3760 https://access.redhat.com/errata/RHSA-2018:3760
Mitigation: * ImageMagick relies on ghostscript when processing certain files formats. Thus, ImageMagick can be used as an attack vector. In order to prevent ImageMagick from processing those files on Red Hat Enterprise Linux 6 and 7, you can disable the use of ghostscript and the processing of PS, EPS, PDF, and XPS file formats in ImageMagick's security policy by opening /etc/ImageMagick/policy.xml and adding the following lines to the "<policymap>" section of the file: ``` <policy domain="coder" rights="none" pattern="PS" /> <policy domain="coder" rights="none" pattern="EPS" /> <policy domain="coder" rights="none" pattern="PDF" /> <policy domain="coder" rights="none" pattern="XPS" /> <policy domain="delegate" rights="none" pattern="gs" /> ``` * Additionally, this issue can be triggered when processing files in order to generate thumbnails, for example when browsing a folder containing a malicious PostScript file in Nautilus. To prevent this, remove or rename the "/usr/bin/evince-thumbnailer" executable. In Red Hat Enterprise Linux v.7.6 and above, the thumbnailing is done in a sandbox. * It is possible to run PDF/PS viewers, such as evince and okular, in a SELinux sandbox using the `sandbox` command from the policycoreutils-sandbox package : $ sandbox -X evince <untrusted-file.pdf> The sandbox will prevent an attacker to make modifications on the file system.