CVE-2021-23140: 
Gallagher Command Centre vulnerability analysis and mitigation

Improper Authorization vulnerability (CVE-2021-23140) was identified in Gallagher Command Centre Server that allows command line macros to be modified by an unauthorized Command Centre Operator. The vulnerability affects multiple versions of Gallagher Command Centre including 8.40 versions prior to 8.40.1888 (MR3), 8.30 versions prior to 8.30.1359 (MR3), 8.20 versions prior to 8.20.1259 (MR5), and version 8.10 and prior versions (NVD, Gallagher Advisory).

The vulnerability has been assigned a CVSS v3.1 base score of 9.9 (CRITICAL) by Gallagher Group Ltd. with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L, indicating network accessibility, low attack complexity, low privileges required, no user interaction needed, and critical impact on confidentiality and integrity with low impact on availability. The NVD assessment differs slightly with a CVSS score of 8.8 (HIGH) and vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (NVD).

The vulnerability allows unauthorized modification of command line macros in the Command Centre Server, potentially compromising the system's security controls and operations. The critical CVSS score indicates severe potential impacts on both confidentiality and integrity of the system (Gallagher Advisory).

According to Gallagher's security advisory, there has been no active exploitation of this vulnerability observed in the wild at the time of publication. The vulnerability requires low attack complexity and only low-level privileges to exploit, making it relatively accessible to attackers (Gallagher Advisory).

Sites not using command line macros are not impacted by this vulnerability. For affected systems, Gallagher has released maintenance updates: v8.40.1888(MR3) for v8.40, v8.30.1359(MR3) for v8.30, and v8.20.1259(MR5) for v8.20. These maintenance upgrades require the Command Centre server to be upgraded (Gallagher Advisory).