Summary

Log4j versions prior to 2.16.0 are subject to a remote code execution vulnerability via the ldap JNDI parser. As per Apache's Log4j security guide: Apache Log4j2 <=2.14.1 JNDI features used in configuration, log messages, and parameters do not protect against attacker controlled LDAP and other JNDI related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled. From log4j 2.16.0, this behavior has been disabled by default.

Log4j version 2.15.0 contained an earlier fix for the vulnerability, but that patch did not disable attacker-controlled JNDI lookups in all situations. For more information, see the Updated advice for version 2.16.0 section of this advisory.

Impact

Logging untrusted or user controlled data with a vulnerable version of Log4J may result in Remote Code Execution (RCE) against your application. This includes untrusted data included in logged errors such as exception traces, authentication failures, and other unexpected vectors of user controlled input.

Affected versions

Any Log4J version prior to v2.15.0 is affected to this specific issue.

The v1 branch of Log4J which is considered End Of Life (EOL) is vulnerable to other RCE vectors so the recommendation is to still update to 2.16.0 where possible.

Security releases Additional backports of this fix have been made available in versions 2.3.1, 2.12.2, and 2.12.3

Affected packages Only the org.apache.logging.log4j:log4j-core package is directly affected by this vulnerability. The org.apache.logging.log4j:log4j-api should be kept at the same version as the org.apache.logging.log4j:log4j-core package to ensure compatability if in use.

Remediation Advice

Updated advice for version 2.16.0

The Apache Logging Services team provided updated mitigation advice upon the release of version 2.16.0, which disables JNDI by default and completely removes support for message lookups. Even in version 2.15.0, lookups used in layouts to provide specific pieces of context information will still recursively resolve, possibly triggering JNDI lookups. This problem is being tracked as CVE-2021-45046. More information is available on the GitHub Security Advisory for CVE-2021-45046.

Users who want to avoid attacker-controlled JNDI lookups but cannot upgrade to 2.16.0 must ensure that no such lookups resolve to attacker-provided data and ensure that the the JndiLookup class is not loaded.

Please note that Log4J v1 is End Of Life (EOL) and will not receive patches for this issue. Log4J v1 is also vulnerable to other RCE vectors and we recommend you migrate to Log4J 2.16.0 where possible.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities are due to insufficient validation of certain elements within a Webex recording that is stored in either the Advanced Recording Format (ARF) or the Webex Recording Format (WRF). An attacker could exploit these vulnerabilities by sending a malicious ARF or WRF file to a user through a link or email attachment and persuading the user to open the file on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities are due to insufficient validation of certain elements within a Webex recording that is stored in either the Advanced Recording Format (ARF) or the Webex Recording Format (WRF). An attacker could exploit these vulnerabilities by sending a malicious ARF or WRF file to a user through a link or email attachment and persuading the user to open the file on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

A vulnerability in Cisco WebEx Business Suite clients, Cisco WebEx Meetings, and Cisco WebEx Meetings Server could allow an authenticated, remote attacker to execute arbitrary code on a targeted system. The vulnerability is due to insufficient input validation by the Cisco WebEx clients. An attacker could exploit this vulnerability by providing meeting attendees with a malicious Flash (.swf) file via the file-sharing capabilities of the client. Exploitation of this vulnerability could allow arbitrary code execution on the system of a targeted user. This affects the clients installed by customers when accessing a WebEx meeting. The following client builds of Cisco WebEx Business Suite (WBS30, WBS31, and WBS32), Cisco WebEx Meetings, and Cisco WebEx Meetings Server are impacted: Cisco WebEx Business Suite (WBS31) client builds prior to T31.23.2, Cisco WebEx Business Suite (WBS32) client builds prior to T32.10, Cisco WebEx Meetings with client builds prior to T32.10, Cisco WebEx Meetings Server builds prior to 2.8 MR2. Cisco Bug IDs: CSCvg19384, CSCvi10746.

A vulnerability in the folder permissions of Cisco Webex Meetings client for Windows could allow an authenticated, local attacker to modify locally stored files and execute code on a targeted device with the privilege level of the user. The vulnerability is due to folder permissions that grant a user the permission to read, write, and execute files in the Webex folders. An attacker could exploit this vulnerability to write malicious files to the Webex client directory, affecting all other users of the targeted device. A successful exploit could allow a user to execute commands with elevated privileges. Attacks on single-user systems are less likely to occur, as the attack must be carried out by the user on the user's own system. Multiuser systems have a higher risk of exploitation because folder permissions have an impact on all users of the device. For an attacker to exploit this vulnerability successfully, a second user must execute the locally installed malicious file to allow remote code execution to occur.

A vulnerability in the Cisco Webex Network Recording Player for Microsoft Windows and the Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerability exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file via a link or an email attachment and persuading the user to open the file by using the affected software. A successful exploit could allow the attacker to execute arbitrary code on the affected system.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

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Multiple vulnerabilities in the user interface of Cisco Webex Meetings Desktop App could allow an authenticated, remote attacker to obtain restricted information from other Webex users. These vulnerabilities are due to improper input validation of parameters returned to the application from a web site. An attacker with a valid Webex account could exploit these vulnerabilities by persuading a user to follow a URL that is designed to return malicious path parameters to the affected software. A successful exploit could allow the attacker to obtain restricted information from other Webex users.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Windows and Cisco Webex Player for Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities are due to insufficient validation of certain elements of a Webex recording that is stored in the Advanced Recording Format (ARF) or Webex Recording Format (WRF). An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Multiple vulnerabilities in Cisco Webex Network Recording Player for Windows and Cisco Webex Player for Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities are due to insufficient validation of certain elements of a Webex recording that is stored in the Advanced Recording Format (ARF) or Webex Recording Format (WRF). An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

A vulnerability in Cisco Webex Meetings and Cisco Webex Meetings Server could allow an unauthenticated, remote attacker to join a Webex session without appearing on the participant list. This vulnerability is due to improper handling of authentication tokens by a vulnerable Webex site. An attacker could exploit this vulnerability by sending crafted requests to a vulnerable Cisco Webex Meetings or Cisco Webex Meetings Server site. A successful exploit requires the attacker to have access to join a Webex meeting, including applicable meeting join links and passwords. The attacker could then exploit this vulnerability to join meetings, without appearing in the participant list, while having full access to audio, video, chat, and screen sharing capabilities.

A vulnerability in the reclaim host role feature of Cisco Webex Meetings and Cisco Webex Meetings Server could allow an authenticated, remote attacker to take over the host role during a meeting. This vulnerability is due to a lack of protection against brute forcing of the host key. An attacker could exploit this vulnerability by sending crafted requests to a vulnerable Cisco Webex Meetings or Webex Meetings Server site. A successful exploit would require the attacker to have access to join a Webex meeting, including applicable meeting join links and passwords. A successful exploit could allow the attacker to acquire or take over the host role for a meeting.

A vulnerability in the user interface of Cisco Webex Meetings and Cisco Webex Meetings Server Software could allow an authenticated, remote attacker to inject a hyperlink into a meeting invitation email. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by entering a URL into a field in the user interface. A successful exploit could allow the attacker to generate a Webex Meetings invitation email that contains a link to a destination of their choosing. Because this email is sent from a trusted source, the recipient may be more likely to click the link.

A vulnerability in the multimedia viewer feature of Cisco Webex Meetings and Cisco Webex Meetings Server could allow an authenticated, remote attacker to bypass security protections. This vulnerability is due to unsafe handling of shared content within the multimedia viewer feature. An attacker could exploit this vulnerability by sharing a file through the multimedia viewer feature. A successful exploit could allow the attacker to bypass security protections and prevent warning dialogs from appearing before files are offered to other users.

A vulnerability in Cisco Webex Meetings and Cisco Webex Meetings Server could allow an unauthenticated, remote attacker to redirect users to a malicious file. This vulnerability is due to improper validation of URL paths in the application interface. An attacker could exploit this vulnerability by persuading a user to follow a specially crafted URL that is designed to cause Cisco Webex Meetings to include a remote file in the web UI. A successful exploit could allow the attacker to cause the application to offer a remote file to a user, which could allow the attacker to conduct further phishing or spoofing attacks.