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CVE-2018-19185: Mz Automation Libiec61850: Buffer overflow

CVE-2018-19185 is rated critical with a CVSS v3.0 base score of 9.8 and affects Mz Automation Libiec61850. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

An issue has been found in libIEC61850 v1.3. It is a heap-based buffer overflow in BerEncoder_encodeOctetString in mms/asn1/ber_encoder.c. This is exploitable even after CVE-2018-18834 has been patched, with a different dataSetValue sequence than the CVE-2018-18834 attack vector.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-787: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

Affected products

  • Mz Automation Libiec61850: 1.3

References