Bug 1468488 (CVE-2017-1000083) - CVE-2017-1000083 evince: command injection via filename in tar-compressed comics archive
Summary: CVE-2017-1000083 evince: command injection via filename in tar-compressed com...
Alias: CVE-2017-1000083
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 1469528 1469529 1470661
Blocks: 1469101
TreeView+ depends on / blocked
Reported: 2017-07-07 08:54 UTC by Bastien Nocera
Modified: 2021-02-04 00:49 UTC (History)
6 users (show)

Fixed In Version:
Doc Type: If docs needed, set a value
Doc Text:
It was found that evince did not properly sanitize the command line which is run to untar Comic Book Tar (CBT) files, thereby allowing command injection. A specially crafted CBT file, when opened by evince or evince-thumbnailer, could execute arbitrary commands in the context of the evince program.
Clone Of:
Last Closed: 2017-08-03 08:28:10 UTC

Attachments (Terms of Use)
0001-comics-Remove-support-for-tar-and-tar-like-commands.patch (5.13 KB, patch)
2017-07-07 08:54 UTC, Bastien Nocera
no flags Details | Diff

System ID Private Priority Status Summary Last Updated
GNOME Bugzilla 784630 0 Normal RESOLVED (CVE-2017-1000083) Evince command injection vulnerability in CBT handler 2020-09-21 08:12:30 UTC
Red Hat Product Errata RHSA-2017:2388 0 normal SHIPPED_LIVE Important: evince security update 2017-08-01 20:05:32 UTC

Description Bastien Nocera 2017-07-07 08:54:56 UTC
Created attachment 1295228 [details]

From the folks at Project Zero:


The comic book backend in evince 3.24.0 is vulnerable to a command injection bug that can be used to execute arbitrary commands when a cbt file is opened:

cbt files are simple tar archives containing images. When a cbt file is processed, evince calls 
"tar -xOf $archive $filename" for every image file in the archive:

// backend/comics/comics-document.c: 914
        command_line = g_strdup_printf ("%s %s %s",

While both the archive name and the filename are quoted to not be interpreted by the shell,
the filename is completely attacker controlled an can start with "--" which leads to tar interpreting it
as a command line flag. 

This can be exploited by creating a tar archive with an embedded file named

Please credit Felix Wilhelm from the Google Security Team in all releases, patches and advisories related to this issue.


All current versions of evince in Fedora and RHEL are vulnerable.

The attached patch will be applied to all versions of Fedora except Fedora 26 and rawhide for which we will use a backport of the comics archive handling rework (https://bugzilla.gnome.org/show_bug.cgi?id=720742).

Comment 1 Bastien Nocera 2017-07-07 13:49:15 UTC
I have the repos ready to commit for f24, f25, f26, rawhide, as well as rhel-7.4. rhel-7.3 is also vulnerable, and I don't know how you want that one handled.

RHEL 6.x is not vulnerable as the CBT feature did not exist (added in evince 2.29.3).

Comment 2 Bastien Nocera 2017-07-10 11:59:59 UTC
There is no CVE filed or assigned, and no attempts have been made to contact other distributions.

Comment 3 Cedric Buissart 2017-07-10 12:43:12 UTC

Name: Felix Wilhelm (Google Security Team)

Comment 4 Bastien Nocera 2017-07-10 14:36:36 UTC
The problem exists in the upstream evince since:
commit d68a91467efab8ef8a8f98589dd4c21b993b6e14
Author: Juanjo Marín <juanj.marin>
Date:   Fri Dec 11 14:40:43 2009 +0100

    [comics] Add support for cbt files
    Fixes bgo#588266.

Which was in the tarball for evince 2.29.4.

atril, the evince fork from the MATE desktop is vulnerable from the day it forked from evince, and still is today:

Adding Michael Catanzaro from the GNOME security and release teams to the CC:.

Comment 8 Cedric Buissart 2017-07-12 14:50:12 UTC

- Disabling evince-thumbnailer to render icons will reduce the attack surface (removing /usr/share/thumbnailers/evince.thumbnailer).
- SELinux  in enforcing mode partially restricts evince-thumbnailer

Comment 10 Cedric Buissart 2017-07-13 12:15:04 UTC
Created evince tracking bugs for this issue:

Affects: fedora-all [bug 1470661]

Comment 11 Bastien Nocera 2017-07-13 13:23:31 UTC
(In reply to Cedric Buissart from comment #10)
> Created evince tracking bugs for this issue:
> Affects: fedora-all [bug 1470661]

FWIW, this was created too late, and all the Fedora updates reference this bug instead.

Comment 13 errata-xmlrpc 2017-08-01 23:48:01 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:2388 https://access.redhat.com/errata/RHSA-2017:2388

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