# What is CVE-2022-20751? > CVE-2022-20751 is a high-severity flaw (CVSS 7.5) in Firepower Threat Defense from Cisco, published on 3 May 2022. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 1.4%. If you run an affected version, plan in the vendor’s fix. Canonical page: https://www.precursorintelligence.com/what-is/cve-2022-20751 ## At a glance - **Verdict:** Plan it in. No sign of exploitation and a low forecast. Patch it in your normal update cycle. - **Precursor Intelligence risk score:** 47 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes. - **Severity:** High (CVSS 7.5 out of 10) - **Known to be exploited:** No, not on the list of flaws known to be exploited today - **Chance of use in the next 30 days:** 1.4% (latest exploit-likelihood forecast) - **Published:** 3 May 2022 - **Record last updated:** 7 November 2023 - **Main product:** Firepower Threat Defense from Cisco - **Affected products:** 23 ## What is CVE-2022-20751? In plain terms It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can take it offline. ### The official description A vulnerability in the Snort detection engine integration for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause unlimited memory consumption, which could lead to a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient memory management for certain Snort events. An attacker could exploit this vulnerability by sending a series of crafted IP packets that would generate specific Snort events on an affected device. A sustained attack could cause an out of memory condition on the affected device. A successful exploit could allow the attacker to interrupt all traffic flowing through the affected device. In some circumstances, the attacker may be able to cause the device to reload, resulting in a DoS condition. ### What kind of flaw is it? - CWE-770: Allocation of Resources Without Limits or Throttling ### How an attack on it works - Where an attacker can be: Anywhere on the internet - How hard it is to pull off: Easy: no special conditions - Login needed first: No login needed - Does someone have to click: No, nobody has to do anything - What an attacker gets: Can take it offline Severity vector: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H` ## Is CVE-2022-20751 being exploited? Not that we know of It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 1.4%. That can change at any time, which is why we keep watching. Exploit likelihood over the last 7 days: 1.4%, 1.4%, 1.4%, 1.4%, 1.4%, 1.4%, 1.4%. ### Timeline - 3 May 2022: Published - 7 November 2023: Record last updated ### How Precursor Intelligence ranks it CVE-2022-20751 scores **47 out of 100 (Medium)**, with the action "Plan remediation". Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less: - Evidence it is being exploited: biggest factor - How severe it is: strong factor - How widely exposed it is: smaller factor - Threat activity around it: smaller factor 85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it. ## Who is affected by CVE-2022-20751? The published record lists 23 products. Versions are as published: "before 6.4.0.15" means every version up to, but not including, 6.4.0.15. - [Firepower Threat Defense](https://www.precursorintelligence.com/product/cisco/firepower_threat_defense) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): before 6.4.0.15, 6.5.0 to before 6.6.5.2, 7.0.0 to before 7.0.2, 7.1.0.0 - [Firepower 1000](https://www.precursorintelligence.com/product/cisco/firepower_1000) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 1010](https://www.precursorintelligence.com/product/cisco/firepower_1010) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 1020](https://www.precursorintelligence.com/product/cisco/firepower_1020) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 1030](https://www.precursorintelligence.com/product/cisco/firepower_1030) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 1040](https://www.precursorintelligence.com/product/cisco/firepower_1040) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 1120](https://www.precursorintelligence.com/product/cisco/firepower_1120) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 1140](https://www.precursorintelligence.com/product/cisco/firepower_1140) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 1150](https://www.precursorintelligence.com/product/cisco/firepower_1150) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 2100](https://www.precursorintelligence.com/product/cisco/firepower_2100) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 2110](https://www.precursorintelligence.com/product/cisco/firepower_2110) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 2120](https://www.precursorintelligence.com/product/cisco/firepower_2120) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 2130](https://www.precursorintelligence.com/product/cisco/firepower_2130) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 2140](https://www.precursorintelligence.com/product/cisco/firepower_2140) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4100](https://www.precursorintelligence.com/product/cisco/firepower_4100) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4110](https://www.precursorintelligence.com/product/cisco/firepower_4110) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4112](https://www.precursorintelligence.com/product/cisco/firepower_4112) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4115](https://www.precursorintelligence.com/product/cisco/firepower_4115) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4120](https://www.precursorintelligence.com/product/cisco/firepower_4120) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4125](https://www.precursorintelligence.com/product/cisco/firepower_4125) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4140](https://www.precursorintelligence.com/product/cisco/firepower_4140) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4145](https://www.precursorintelligence.com/product/cisco/firepower_4145) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Firepower 4150](https://www.precursorintelligence.com/product/cisco/firepower_4150) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified ## How do I fix CVE-2022-20751? 1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list. 2. **Apply the vendor’s fix.** Install the update named in the vendor’s advisory. We’ve put the advisory first in the list. 3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in. 4. **Keep an eye on it.** Track the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood. ### References - [tools.cisco.com](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-snort-dos-hd2hFgM) (Vendor advisory) ## Questions ### What is CVE-2022-20751? CVE-2022-20751 is a high-severity flaw in Firepower Threat Defense from Cisco, published on 3 May 2022. It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can take it offline. ### How serious is CVE-2022-20751? It scores 7.5 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2022-20751 is 47 out of 100, which is Medium. Its action is "Plan remediation". No sign of exploitation and a low forecast. Patch it in your normal update cycle. ### Is CVE-2022-20751 being exploited? It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 1.4%. That can change at any time, which is why we keep watching. ### Which versions does CVE-2022-20751 affect? For Firepower Threat Defense from Cisco: before 6.4.0.15, 6.5.0 to before 6.6.5.2, 7.0.0 to before 7.0.2, 7.1.0.0. The record lists 23 products in all, each with its versions, under "Who is affected" on this page. ### How do I fix CVE-2022-20751? Install the update the vendor names in its advisory, linked first under "How do I fix" on this page. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet. ## Does CVE-2022-20751 affect you? Precursor Intelligence keeps checking for you: - **Tell us what you run.** Pick your software from a list, or let us work it out from your website. - **We match it to every flaw.** Over 400,000 published flaws, checked against your list. - **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it. - **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools. Start free (no card, nothing to install): https://www.precursorintelligence.com/register Book a demo: https://www.precursorintelligence.com/contact