9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8 High
AI Score
Confidence
High
10 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
0.171 Low
EPSS
Percentile
96.0%
This updated advisory is a follow-up to the original advisory titled ICSA-19-099-04 Siemens SINEMA Remote Connect that was published April 9, 2019, to the ICS webpage on us-cert.cisa.gov.
Successful exploitation of these vulnerabilities could allow an attacker to circumvent the system authorization for certain functionalities, and to execute privileged functions.
The following Siemens products are affected:
Note that not every product listed above is affected by every vulnerability described below. Please see the Siemens advisory for more detail.
4.2.1 INCORRECT CALCULATION OF BUFFER SIZE CWE-131
The HTTP client curl is vulnerable to a buffer overrun.
The vulnerability could be exploited by an attacker providing a malicious HTTP server. Successful exploitation requires no system privileges. User interaction by a legitimate use is required to exploit the vulnerability. An attacker could use the vulnerability to compromise confidentiality, integrity and availability of the affected device.
CVE-2018-14618 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H)
4.2.2 OUT-OF-BOUNDS READ CWE-125
The HTTP client library libcurl is vulnerable to a heap buffer out-of-bounds read.
The vulnerability could be exploited by an attacker providing a malicious HTTP server. Successful exploitation requires no system privileges and no user interaction. An attacker could use the vulnerability to compromise availability of the affected system.
CVE-2018-16890 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
4.2.3 STACK-BASED BUFFER OVERFLOW CWE-121
The HTTP client library libcurl is vulnerable to a stack-based buffer overflow.
The vulnerability could be exploited by an attacker providing a malicious HTTP server. Successful exploitation requires no system privileges and no user interaction. An attacker could use the vulnerability to compromise confidentiality, integrity and availability of the affected system.
CVE-2019-3822 has been assigned to this vulnerability. A CVSS v3 base score of 8.1 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).
--------- Begin Update A Part 1 of 1 ---------
The libcurl library versions 7.34.0 to and including 7.63.0 are vulnerable to a heap out-of-bounds read in the code handling the end-of-response for SMTP. This vulnerability could allow an attacker to trigger a denial-of-service condition on the affected devices.
CVE-2019-3823 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
--------- End Update A Part 1 of 1 ---------
4.2.5 IMPROPER HANDLING OF INSUFFICIENT PERMISSIONS CWE-280
Due to insufficient checking of user permissions, an attacker may access URLs that require special authorization.
The vulnerability could be exploited by an attacker with network access to the affected system. An attacker must have access to a low privileged account to exploit the vulnerability. An attacker could use the vulnerability to compromise confidentiality, integrity and availability of the affected system.
CVE-2019-6570 has been assigned to this vulnerability. A CVSS v3 base score of 8.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H).
Siemens ProductCERT reported these vulnerabilities to CISA.
Siemens currently has updates for the following products:
Siemens recommends users apply the following specific workarounds and mitigations to reduce the risk:
Siemens recommends users configure their environment according to Siemens’ operational guidelines for industrial security and follow the recommendations in the product manuals.
Additional information on industrial security by Siemens can be found at: <https://www.siemens.com/industrialsecurity>
For more information on these vulnerabilities and more detailed mitigation instructions, please see Siemens Security Advisory SSA-436177
For further inquiries on security vulnerabilities in Siemens products and solutions, please contact Siemens ProductCERT.
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should:
CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
CISA also provides a section for control systems security recommended practices on the ICS webpage on us-cert.cisa.gov. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.
Additional mitigation guidance and recommended practices are publicly available on the ICS webpage on us-cert.cisa.gov in the Technical Information Paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies.
Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to CISA for tracking and correlation against other incidents.
No known public exploits specifically target these vulnerabilities.
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2018-14618
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2018-16890
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-3822
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-3823
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-6570
www.siemens.com/cert/advisories
assets.new.siemens.com/siemens/assets/public.1502968141.411e91564a2d259ecd4b6c79b51f89c044b3de81.operational-guidelines-industrial-security-en.pdf
cert-portal.siemens.com/productcert/pdf/ssa-436177.pdf
cwe.mitre.org/data/definitions/121.html
cwe.mitre.org/data/definitions/125.html
cwe.mitre.org/data/definitions/125.html
cwe.mitre.org/data/definitions/131.html
cwe.mitre.org/data/definitions/280.html
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
support.industry.siemens.com/cs/de/en/view/109764829
support.industry.siemens.com/cs/de/en/view/109764829
twitter.com/CISAgov
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us-cert.cisa.gov/ics
us-cert.cisa.gov/ics
us-cert.cisa.gov/ics/alerts/ICS-ALERT-10-301-01
us-cert.cisa.gov/ics/recommended-practices
us-cert.cisa.gov/ics/tips/ICS-TIP-12-146-01B
us-cert.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf
www.dhs.gov
www.dhs.gov/foia
www.dhs.gov/performance-financial-reports
www.facebook.com/CISA
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mailto:?subject=Siemens%20SINEMA%20Remote%20Connect%20%28Update%20A%29&body=www.cisa.gov/news-events/ics-advisories/icsa-19-099-04
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8 High
AI Score
Confidence
High
10 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
0.171 Low
EPSS
Percentile
96.0%