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CVE-2018-1000140: Rsyslog Librelp: Buffer overflow

CVE-2018-1000140 is rated critical with a CVSS v3.0 base score of 9.8 and affects Rsyslog Librelp, along with 8 other products in NVD’s configuration data. 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

rsyslog librelp version 1.2.14 and earlier contains a Buffer Overflow vulnerability in the checking of x509 certificates from a peer that can result in Remote code execution. This attack appear to be exploitable a remote attacker that can connect to rsyslog and trigger a stack buffer overflow by sending a specially crafted x509 certificate.

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

  • Rsyslog Librelp: up to and including 1.2.14
  • Debian Linux: 8.0; 9.0
  • Canonical Ubuntu Linux: 14.04
  • Red Hat Enterprise Linux Desktop: 6.0; 7.0
  • Red Hat Enterprise Linux Server: 6.0; 7.0
  • Red Hat Enterprise Linux Server Aus: 6.6; 7.2; 7.3; 7.4; 7.6
  • Red Hat Enterprise Linux Server Eus: 6.7; 7.3; 7.4; 7.5; 7.6
  • Red Hat Enterprise Linux Server Tus: 6.6; 7.2; 7.3; 7.4; 7.6
  • Red Hat Enterprise Linux Workstation: 6.0; 7.0

References