CVE-2020-27121 Explained : Impact and Mitigation
Learn about CVE-2020-27121, a vulnerability in Cisco Unified Communications Manager IM & Presence Service allowing DoS attacks. Find mitigation steps and long-term security practices.
A vulnerability in Cisco Unified Communications Manager IM & Presence Service could allow an authenticated, remote attacker to cause a denial of service (DoS) condition.
Understanding CVE-2020-27121
This CVE involves a vulnerability in Cisco Unified Communications Manager IM & Presence Service that could lead to a DoS attack.
What is CVE-2020-27121?
The vulnerability allows an authenticated remote attacker to restart the Cisco XCP Authentication Service on an affected device, resulting in a DoS condition. It stems from improper handling of login requests.
The Impact of CVE-2020-27121
- An attacker can exploit this vulnerability by sending a crafted client login request, causing a process to crash and resulting in a DoS condition for new login attempts.
- Authenticated users at the time of the attack are not affected.
- Workarounds are available to address this vulnerability.
Technical Details of CVE-2020-27121
This section provides more technical insights into the CVE.
Vulnerability Description
The vulnerability in Cisco Unified Communications Manager IM & Presence Service allows for a DoS attack due to improper login request handling.
Affected Systems and Versions
- Product: Cisco Unified Communications Manager IM and Presence Service
- Vendor: Cisco
- Version: Not applicable
Exploitation Mechanism
- Attack Complexity: Low
- Attack Vector: Network
- Privileges Required: Low
- User Interaction: None
- Scope: Unchanged
- CVSS Base Score: 4.3 (Medium Severity)
- Vector String: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Mitigation and Prevention
Protecting systems from CVE-2020-27121 is crucial to prevent potential DoS attacks.
Immediate Steps to Take
- Apply workarounds provided by Cisco to mitigate the vulnerability.
- Monitor for any unusual login requests or system restarts.
Long-Term Security Practices
- Regularly update and patch the affected systems.
- Implement network segmentation and access controls to limit exposure.
Patching and Updates
- Stay informed about security advisories and updates from Cisco.
- Apply patches promptly to address known vulnerabilities.