CVE-2018-0296: Vulnerability in Cisco ASA and Firepower Appliances Sees Spike in Exploit Attempts
The Cisco Adaptive Security Appliance and Firepower Appliance vulnerability patched over a year ago continues to be targeted by attackers in the wild, as exploitation attempts have increased in frequency over the past several weeks.
Background
On December 20, researchers at Cisco Talos published a blog post warning that a previously patched flaw in Cisco Adaptive Security Appliance (ASA) and Firepower Appliance has seen “a sudden spike in exploitation attempts.”
Analysis
CVE-2018-0296 is an improper input validation vulnerability in the ASA web interface. An unauthenticated, remote attacker could exploit this flaw by sending a specially crafted HTTP request to a vulnerable ASA or Firepower device. This results in unexpected reloads of the device, causing a denial of service (DoS) condition. However, in certain software versions of the ASA or Firepower Threat Defense (FTD), a reload will not occur, but an attacker could view sensitive information by sending a specially crafted HTTP request containing directory traversal sequences.
The vulnerability was originally patched on June 6, 2018, after it was disclosed by security researcher Michal Bentkowski of Securitum, who published a blog post detailing his findings soon after. Roughly translated, Bentkowski noted the following in his post, “The error was reported to Cisco just on the example as above, i.e. the possibility of obtaining information about logged in users.” This differed from Cisco’s public description of the vulnerability, which focused on DoS and mentioned the possibility of directory traversal in some instances, the latter potentially related to Bentkowski’s findings. Cisco updated the advisory for the flaw on June 22, 2018, announcing they had observed public exploitation of the vulnerability.
In March 2019, Cisco updated the advisory once again, and in April 2019, the vulnerability was identified as one of the flaws used in a DNS hijacking campaign called Sea Turtle.
Cisco issued a final update to their advisory on September 24, 2019, elevating the vulnerability to critical after observing more exploitation attempts.
Proof of concept
The first proof of concept (PoC) for the vulnerability was published to GitHub on June 21, 2018, and was regularly updated, accepting pull requests all the way up until March 2019. The repository has not been updated since June 2019.
There have been other PoCs for CVE-2018-0296 published to GitHub, including an exploit script to enumerate usernames from vulnerable devices and another exploit script called the Cisco Pillager.
Solution
As previously mentioned, the vulnerability was patched back in June 2018. The following devices running Cisco ASA or FTD software are potentially vulnerable:
| Device | Status |
|---|---|
| Cisco Industrial Security Appliance 3000 (ISA) | Supported |
| Cisco ASA 1000V Cloud Firewall | End-of-Life |
| Cisco ASA 5500 Series Adaptive Security Appliances | Supported |
| Cisco ASA 5500-X Series Next-Generation Firewalls | Supported |
| Cisco Catalyst 6500 Series Switches ASA Services Module | Supported |
| Cisco 7600 Series Routers ASA Services Module | End of Life |
| Cisco Adaptive Security Virtual Appliance (ASAv) | Supported |
| Cisco Firepower 2100 Series Security Appliance | Supported |
| Cisco Firepower 4100 Series Security Appliance | Supported |
| Cisco Firepower 9300 Security Appliance | Supported |
| Cisco Firepower Threat Defense Virtual (FTDv) | Supported |
The devices may be vulnerable depending on the ASA or FTD software features and configuration. For a detailed breakdown of the features and configurations, please refer to the affected products section under Cisco’s advisory.
Identifying affected systems
A list of Tenable plugins to identify this vulnerability can be found here.
Get more information
- Cisco Talos Blog Post on Recent Spike in Exploit Attempts for CVE-2018-0296
- Cisco Advisory for CVE-2018-0296
- Michał Bentkowski's Blog Post on CVE-2018-0296
- Yassine Aboukir's PoC for CVE-2018-0296
Join Tenable's Security Response Team on the Tenable Community.
Learn more about Tenable, the first Cyber Exposure platform for holistic management of your modern attack surface.
Get a free 30-day trial of Tenable.io Vulnerability Management.
Related Articles
Volt Typhoon: U.S. Critical Infrastructure Targeted by State-Sponsored Actors
November 19, 2024Volt Typhoon, a state-sponsored actor linked to the People’s Republic of China, has consistently targeted U.S. critical infrastructure with the intent to maintain persistent access. Tenable Research examines the tactics, techniques and procedures of this threat actor.
CVE-2024-0012, CVE-2024-9474: Zero-Day Vulnerabilities in Palo Alto PAN-OS Exploited In The Wild
November 18, 2024Palo Alto Networks confirmed two zero-day vulnerabilities were exploited as part of attacks in the wild against PAN-OS devices, with one being attributed to Operation Lunar Peek.
Microsoft’s November 2024 Patch Tuesday Addresses 87 CVEs (CVE-2024-43451, CVE-2024-49039)
November 12, 2024Microsoft addresses 87 CVEs and one advisory (ADV240001) in its November 2024 Patch Tuesday release, with four critical vulnerabilities and four zero-day vulnerabilities, including two that were exploited in the wild.
Active Directory Under Attack: Five Eyes Guidance Targets Crucial Security Gaps
November 21, 2024A landmark global report from cybersecurity agencies emphasizes 17 attack techniques against Microsoft Active Directory and cautions organizations to step up protections. In the first of our two-part series, we offer five steps you can take today to shore up your AD defenses.
Five Cyber Agencies Sound Alarm About Active Directory Attacks: Beyond the Basics
November 21, 2024A landmark global report emphasizes 17 attack techniques against Microsoft Active Directory and cautions organizations to step up protections. In the second of our two-part series, we take you beyond the basics to highlight three key areas to focus on.
Volt Typhoon: What State and Local Government Officials Need to Know
November 19, 2024Increased activity from the state-sponsored threat group Volt Typhoon raises concerns about the cybersecurity of U.S. critical infrastructure. Here’s how you can identify potential exposures and attack paths.
- Vulnerability Management