Summary

• A vulnerability in how Cisco Firepower Threat Defense (FTD) Software handles session timeouts for management connections could allow an unauthenticated, remote attacker to cause a buildup of remote management connections to an affected device, which could result in a denial of service (DoS) condition.

  The vulnerability exists because the default session timeout period for specific to-the-box remote management connections is too long. An attacker could exploit this vulnerability by sending a large and sustained number of crafted remote management connections to an affected device, resulting in a buildup of those connections over time. A successful exploit could allow the attacker to cause the remote management interface or Cisco Firepower Device Manager (FDM) to stop responding and cause other management functions to go offline, resulting in a DoS condition. The user traffic that is flowing through the device would not be affected, and the DoS condition would be isolated to remote management only.

  There are no workarounds that address this vulnerability.

  This advisory is available at the following link:
  https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-mgmt-interface-dos-FkG4MuTU

Affected Products

• Vulnerable Products

  At the time of publication, this vulnerability affected Cisco FTD Software releases earlier than Release 6.4.0.9 and Release 6.5.0.5.

  For information about which Cisco software releases are vulnerable, see the Fixed Software section of this advisory. See the Details section in the bug ID(s) at the top of this advisory for the most complete and current information.

  Products Confirmed Not Vulnerable

  Only products listed in the Vulnerable Products section of this advisory are known to be affected by this vulnerability.

  Cisco has confirmed that this vulnerability does not affect Cisco Adaptive Security Appliance (ASA) Software or Cisco Firepower Management Center (FMC) Software.

Indicators of Compromise

• If this vulnerability is being exploited, administrators may see the following system error logging message on the console or in the logging file:

  HTTP: [mpm_worker:error] server reached MaxRequestWorkers setting, consider raising the MaxRequestWorkers setting

  Administrators are advised to contact the Cisco Technical Assistance Center (TAC) to review the device logs to determine if this vulnerability is being exploited.

Workarounds

• There are no workarounds that address this vulnerability.

Fixed Software

• When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories and Alerts page, to determine exposure and a complete upgrade solution.

  In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.

  Fixed Releases

  At the time of publication, the release information in the following table(s) was accurate. See the Details section in the bug ID(s) at the top of this advisory for the most complete and current information.

  The left column lists Cisco software releases, and the right column indicates whether a release was affected by the vulnerability described in this advisory and which release included the fix for this vulnerability.

  Cisco FTD Software

  Cisco FTD Software Release	First Fixed Release for This Vulnerability
  Earlier than 6.1.01	Migrate to a fixed release.
  6.1.0	Migrate to a fixed release.
  6.2.0	Migrate to a fixed release.
  6.2.1	Migrate to a fixed release.
  6.2.2	Migrate to a fixed release.
  6.2.3	Migrate to a fixed release.
  6.3.0	Migrate to a fixed release.
  6.4.0	6.4.0.9
  6.5.0	6.5.0.5 (future release) Cisco_FTD_Hotfix_H-6.5.0.5-2.sh.REL.tar and later Cisco_FTD_SSP_FP1K_Hotfix_H-6.5.0.5-2.sh.REL.tar and later Cisco_FTD_SSP_FP2K_Hotfix_H-6.5.0.5-2.sh.REL.tar and later Cisco_FTD_SSP_Hotfix_H-6.5.0.5-2.sh.REL.tar and later
  6.6.0	Not vulnerable.

  1. Cisco FMC and FTD Software releases 6.0.1 and earlier have reached end of software maintenance. Customers are advised to migrate to a supported release that includes the fix for this vulnerability.

  To upgrade to a fixed release of Cisco FTD Software, customers can do one of the following:

  • For devices that are managed by using Cisco Firepower Management Center (FMC), use the FMC interface to install the upgrade. After installation is complete, reapply the access control policy.
  • For devices that are managed by using Cisco Firepower Device Manager (FDM), use the FDM interface to install the upgrade. After installation is complete, reapply the access control policy.

Exploitation and Public Announcements

• The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

Source

• This vulnerability was found by Santosh Krishnamurthy of Cisco during internal security testing.

URL

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-mgmt-interface-dos-FkG4MuTU

Revision History

• Version	Description	Section	Status	Date
  1.1	Updated Hot Fixes for FTD releases 6.4.0 and 6.5.0.	Fixed Releases	Final	2020-MAY-15
  1.2	Updated fixed release information for FTD Release 6.4.0.	Fixed Releases	Final	2020-MAY-06
  1.0	Initial public release.	-	Final	2020-MAY-06

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