1. EXECUTIVE SUMMARY
- CVSS v3 10.0
- ATTENTION: Exploitable remotely
- Vendor: Treck Inc.
- Equipment: TCP/IP
- Vulnerabilities: Improper Handling of Length Parameter Inconsistency, Improper Input Validation, Double Free, Out-of-bounds Read, Integer Overflow or Wraparound, Improper Null Termination, Improper Access Control
CISA is aware of a public report, known as “Ripple20” that details vulnerabilities found in the Treck TCP/IP stack. CISA is issuing this advisory to provide early notice of the reported vulnerabilities and identify baseline mitigations for reducing risks to these and other cybersecurity attacks.
The Treck TCP/IP stack may be known by other names such as Kasago TCP/IP, ELMIC, Net+ OS, Quadnet, GHNET v2, Kwiknet, or AMX.
2. UPDATE INFORMATION
This updated advisory is a follow-up to the original advisory titled ICSA-20-168-01 Treck TCP/IP Stack (Update E) that was published July 21, 2020, to the ICS webpage on us-cert.gov.
3. RISK EVALUATION
Successful exploitation of these vulnerabilities may allow remote code execution or exposure of sensitive information.
4. TECHNICAL DETAILS
4.1 AFFECTED PRODUCTS
The Treck TCP/IP stack is affected including:
- IPv4
- IPv6
- UDP
- DNS
- DHCP
- TCP
- ICMPv4
- ARP
4.2 VULNERABILITY OVERVIEW
4.2.1 IMPROPER HANDLING OF LENGTH PARAMETER INCONSISTENCY CWE-130
Improper handling of length parameter inconsistency in IPv4/UDP component when handling a packet sent by an unauthorized network attacker. This vulnerability may result in remote code execution.
CVE-2020-11896 has been assigned to this vulnerability. A CVSS v3 base score of 10.0 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H).
4.2.2 IMPROPER HANDLING OF LENGTH PARAMETER INCONSISTENCY CWE-130
Improper handling of length parameter inconsistency in IPv6 component when handling a packet sent by an unauthorized network attacker. This vulnerability may result in possible out-of-bounds write.
CVE-2020-11897 has been assigned to this vulnerability. A CVSS v3 base score of 10.0 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H).
4.2.3 IMPROPER HANDLING OF LENGTH PARAMETER INCONSISTENCY CWE-130
Improper handling of length parameter inconsistency in IPv4/ICMPv4 component when handling a packet sent by an unauthorized network attacker. This vulnerability may result in out-of-bounds Read.
CVE-2020-11898 has been assigned to this vulnerability. A CVSS v3 base score of 9.1 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H).
4.2.4 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in IPv6 component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow out-of-bounds Read and a possible Denial of Service.
CVE-2020-11899 has been assigned to this vulnerability. A CVSS v3 base score of 5.4 has been calculated; the CVSS vector string is (AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L).
4.2.5 DOUBLE FREE CWE-415
Possible double free in IPv4 tunneling component when handling a packet sent by a network attacker. This vulnerability may result in use after free.
CVE-2020-11900 has been assigned to this vulnerability. A CVSS v3 base score of 8.2 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H).
4.2.6 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in DNS resolver component when handling a packet sent by an unauthorized network attacker. This vulnerability may result in remote code execution.
CVE-2020-11901 has been assigned to this vulnerability. A CVSS v3 base score of 9.0 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H).
4.2.7 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in IPv6 over IPv4 tunneling component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow out-of-bounds Read.
CVE-2020-11902 has been assigned to this vulnerability. A CVSS v3 base score of 7.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).
4.2.8 OUT-OF-BOUNDS READ CWE-125
Possible out-of-bounds read in DHCP component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow exposure of sensitive information.
CVE-2020-11903 has been assigned to this vulnerability. A CVSS v3 base score of 5.3 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N).
4.2.9 INTEGER OVERFLOW OR WRAPAROUND CWE-190
Possible integer overflow or wraparound in memory allocation component when handling a packet sent by an unauthorized network attacker may result in out-of-bounds write.
CVE-2020-11904 has been assigned to this vulnerability. A CVSS v3 base score of 5.6 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L).
4.2.10 OUT-OF-BOUNDS READ CWE-125
Possible out-of-bounds read in DHCPv6 component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow exposure of sensitive information.
CVE-2020-11905 has been assigned to this vulnerability. A CVSS v3 base score of 5.3 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N).
4.2.11 IMPROPER INPUT VALIDATION CWE-20
Improper input validation CWE-20 in ethernet link layer component from a packet sent by an unauthorized user.
CVE-2020-11906 has been assigned to this vulnerability. A CVSS v3 base score of 5.0 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L).
4.2.12 IMPROPER HANDLING OF LENGTH PARAMETER INCONSISTENCY CWE-130
Improper handling of length parameter inconsistency in TCP component, from a packet sent by an unauthorized network attacker.
CVE-2020-11907 has been assigned to this vulnerability. A CVSS v3 base score of 5.0 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L).
4.2.13 IMPROPER NULL TERMINATION CWE-170
Improper null termination in DHCP component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow exposure of sensitive information.
CVE-2020-11908 has been assigned to this vulnerability. A CVSS v3 base score of 3.1 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L).
4.2.14 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in IPv4 component when handling a packet sent by an unauthorized network attacker.
CVE-2020-11909 has been assigned to this vulnerability. A CVSS v3 base score of 3.7 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N).
4.2.15 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in ICMPv4 component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow out-of-bounds Read.
CVE-2020-11910 has been assigned to this vulnerability. A CVSS v3 base score of 3.7 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N).
4.2.16 IMPROPER ACCESS CONTROL CWE-284
The affected product is vulnerable to improper access control, which may allow an attacker to change one specific configuration value.
CVE-2020-11911 has been assigned to this vulnerability. A CVSS v3 base score of 3.7 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L).
4.2.17 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in TCP component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow out-of-bounds Read..
CVE-2020-11912 has been assigned to this vulnerability. A CVSS v3 base score of 3.7 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L).
4.2.18 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in IPv6 component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow out-of-bounds Read.
CVE-2020-11913 has been assigned to this vulnerability. A CVSS v3 base score of 3.7 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N).
4.2.19 IMPROPER INPUT VALIDATION CWE-20
Improper input validation in ARP component when handling a packet sent by an unauthorized network attacker. This vulnerability may allow out-of-bounds Read.
CVE-2020-11914 has been assigned to this vulnerability. A CVSS v3 base score of 3.1 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N).
4.3 BACKGROUND
- CRITICAL INFRASTRUCTURE SECTORS: Energy,Critical Manufacturing, Information Technology, Healthcare and Public Health, Transportation Systems
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: United States
4.4 RESEARCHER
Shlomi Oberman and Moshe Kol from JSOF reported these vulnerabilities to CERT/CC.
5. MITIGATIONS
Treck recommends users apply the latest version of the affected products (Treck TCP/IP 6.0.1.67 or later versions). To obtain patches, email security@treck.com
For more detailed information on the vulnerabilities and the mitigating controls, please see the Treck advisory. Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
——— Begin Update G Part 1 of 1 ———
——— End Update G Part 1 of 1 ———
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should:
- Minimize network exposure for all control system devices and/or systems, and ensure that they are not accessible from the Internet.
- Locate control system networks and remote devices behind firewalls, and isolate them from the business network.
- When remote access is required, use secure methods, such as Virtual Private Networks (VPNs), recognizing that VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize that VPN is only as secure as the connected devices.
- Use an internal DNS server that performs DNS-over-HTTPS for lookups.
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.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.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.
High skill level is needed to exploit. No known public exploits specifically target these vulnerabilities.
Source: