SSA-397453: Apache Log4j Vulnerabilities (Log4Shell, CVE-2021-44228, CVE-2021-45046) - Impact to Siemens Energy TraceAlertServerPLUS
Publication Date:
2021-12-20
Last Update:
2021-12-20
Current Version:
V1.0
CVSS v3.1 Base Score:
10.0
SUMMARY
On 2021-12-09, a vulnerability in Apache Log4j (a logging library used in many Java-based applications) was disclosed, that could allow remote unauthenticated attackers to execute code on vulnerable systems. The vulnerability is tracked as CVE-2021-44228 and is also known as “Log4Shell”.
On 2021-12-14 an additional denial of service vulnerability (CVE-2021-45046) was published rendering the initial mitigations and fix in version 2.15.0 as incomplete under certain non-default configurations. Log4j versions 2.16.0 and 2.12.2 are supposed to fix both vulnerabilities.
On 2021-12-17, CVE-2021-45046 was reclassified with an increased CVSS base score (from 3.7 to 9.0). The potential impact of CVE-2021-45046 now includes - besides denial of service - also information disclosure and local (and potential remote) code execution.
Siemens Energy is preparing updates and recommends specific countermeasures for TraceAlertServerPLUS.
AFFECTED PRODUCTS AND SOLUTION
Affected Product and Versions
Remediation
TraceAlertServerPLUS:
All versions
Currently no remediation is availableOpen TraceAlertServerPLUS.exe with Zip tool to remove file JndiLookup.class in directory org/apache/logging/log4j/core/lookup/.
This measure mitigates both CVE-2021-44228 and CVE-2021-45046.
See further recommendations from section Workarounds and Mitigations
WORKAROUNDS AND MITIGATIONS
Siemens has identified the following specific workarounds and mitigations that customers can apply to reduce the risk:
Review the status of the defense in depth recommendations that apply to your specific deployment and align as needed. Especially the measures on the network layer to prevent accessibility from other network segments
Restrict physical access to the local networks of the solution
Ensure that TraceAlertServerPLUS does not run with elevated privileges
Check file system permissions
GENERAL SECURITY RECOMMENDATIONS
Operators of critical power systems (e.g. TSOs or DSOs) worldwide are usually required by regulations to build resilience into the power grids by applying multi-level redundant secondary protection schemes. It is therefore recommended that the operators check whether appropriate resilient protection measures are in place. The risk of cyber incidents impacting the grid’s reliability can thus be minimized by virtue of the grid design.
Siemens strongly recommends applying the provided security updates using the corresponding tooling and documented procedures made available with the product. If supported by the product, an automated means to apply the security updates across multiple product instances may be used. Siemens strongly recommends prior validation of any security update before being applied, and supervision by trained staff of the update process in the target environment.
As a general security measure Siemens strongly recommends to protect network access with appropriate mechanisms (e.g. firewalls, segmentation, VPN). It is advised to configure the environment according to our operational guidelines in order to run the devices in a protected IT environment.
PRODUCT DESCRIPTION
TraceAlertServerPLUS is a software component installed in SVC PLUS energy transmission solutions.
VULNERABILITY CLASSIFICATION
The vulnerability classification has been performed by using the CVSS scoring system in version 3.1
(CVSS v3.1) (https://www.first.org/cvss ). The CVSS environmental score is specific to the customer’s
environment and will impact the overall CVSS score. The environmental score should therefore be
individually defined by the customer to accomplish final scoring.
An additional classification has been performed using the CWE classification, a community-developed
list of common software security weaknesses. This serves as a common language and as a baseline for
weakness identification, mitigation, and prevention efforts. A detailed list of CWE classes can be found
at: https://cwe.mitre.org/ .
Vulnerability CVE-2021-44228
Apache Log4j V2, versions < 2.15.0 do not protect JNDI features (as used in configuration, log messages, and parameters) against attacker controlled LDAP and other JNDI related endpoints.
An attacker who can control log messages or log message parameters could execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled.
CVSS v3.1 Base Score
10.0
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C
CWE:
CWE-20: Improper Input Validation
Vulnerability CVE-2021-45046
The fix to address CVE-2021-44228 was incomplete in certain non-default configurations, when the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, ${ctx:loginId}).
This could allow attackers with control over Thread Context Map (MDC) input data to craft malicious input data using a JNDI Lookup pattern, resulting in an information leak and remote code execution in some environments and local code execution in all environments.
CVSS v3.1 Base Score
9.0
CVSS Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C
CWE:
CWE-20: Improper Input Validation
ADDITIONAL INFORMATION
For further inquiries on security vulnerabilities in Siemens products and solutions, please contact
the Siemens ProductCERT:
https://www.siemens.com/cert/advisories
HISTORY DATA
V1.0 (2021-12-20): Publication Date
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