# What is CVE-2019-1965? > CVE-2019-1965 is a high-severity flaw (CVSS 7.7) in NX-OS from Cisco, published on 28 August 2019. 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 1.5%. If you run an affected version, plan in the vendor’s fix. Canonical page: https://www.precursorintelligence.com/what-is/cve-2019-1965 ## 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:** 46 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes. - **Severity:** High (CVSS 7.7 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:** 1.5% (latest exploit-likelihood forecast) - **Published:** 28 August 2019 - **Record last updated:** 16 October 2020 - **Main product:** NX-OS from Cisco - **Affected products:** 87 ## What is CVE-2019-1965? In plain terms It can be attacked from anywhere on the internet with an ordinary user account, and nobody has to click anything. If it works, the attacker can take it offline. ### The official description A vulnerability in the Virtual Shell (VSH) session management for Cisco NX-OS Software could allow an authenticated, remote attacker to cause a VSH process to fail to delete upon termination. This can lead to a build-up of VSH processes that overtime can deplete system memory. When there is no system memory available, this can cause unexpected system behaviors and crashes. The vulnerability is due to the VSH process not being properly deleted when a remote management connection to the device is disconnected. An attacker could exploit this vulnerability by repeatedly performing a remote management connection to the device and terminating the connection in an unexpected manner. A successful exploit could allow the attacker to cause the VSH processes to fail to delete, which can lead to a system-wide denial of service (DoS) condition. The attacker must have valid user credentials to log in to the device using the remote management connection. ### What kind of flaw is it? - CWE-772: Missing Release of Resource after Effective Lifetime - CWE-400: Uncontrolled Resource Consumption ### 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: An ordinary user account - 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:L/UI:N/S:C/C:N/I:N/A:H` ## Is CVE-2019-1965 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 1.5%. That can change at any time, which is why we keep watching. Exploit likelihood over the last 7 days: 1.5%, 1.5%, 1.5%, 1.5%, 1.5%, 1.5%, 1.5%. ### Timeline - 28 August 2019: Published - 16 October 2020: Record last updated ### How Precursor Intelligence ranks it CVE-2019-1965 scores **46 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-2019-1965? The published record lists 87 products. Versions are as published: "before 7.1(5)n1(1b)" means every version up to, but not including, 7.1(5)n1(1b). - [NX-OS](https://www.precursorintelligence.com/product/cisco/nx-os) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Operating system): before 7.1(5)n1(1b), before 6.2(22), before 7.0(3)i4(9), before 3.2(3k), 4.0 to before 4.0(2e), 5.2 to before 6.2(29), 7.0(3)f to before 9.2 - [7000 10-Slot](https://www.precursorintelligence.com/product/cisco/7000_10-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [7000 18-Slot](https://www.precursorintelligence.com/product/cisco/7000_18-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [7000 4-Slot](https://www.precursorintelligence.com/product/cisco/7000_4-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [7000 9-Slot](https://www.precursorintelligence.com/product/cisco/7000_9-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [7700 10-Slot](https://www.precursorintelligence.com/product/cisco/7700_10-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [7700 18-Slot](https://www.precursorintelligence.com/product/cisco/7700_18-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [7700 2-Slot](https://www.precursorintelligence.com/product/cisco/7700_2-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [7700 6-Slot](https://www.precursorintelligence.com/product/cisco/7700_6-slot) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9132t](https://www.precursorintelligence.com/product/cisco/mds_9132t) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9148s](https://www.precursorintelligence.com/product/cisco/mds_9148s) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9148t](https://www.precursorintelligence.com/product/cisco/mds_9148t) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9216](https://www.precursorintelligence.com/product/cisco/mds_9216) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9216a](https://www.precursorintelligence.com/product/cisco/mds_9216a) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9216i](https://www.precursorintelligence.com/product/cisco/mds_9216i) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9222i](https://www.precursorintelligence.com/product/cisco/mds_9222i) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9250i](https://www.precursorintelligence.com/product/cisco/mds_9250i) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9396s](https://www.precursorintelligence.com/product/cisco/mds_9396s) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9396t](https://www.precursorintelligence.com/product/cisco/mds_9396t) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9506](https://www.precursorintelligence.com/product/cisco/mds_9506) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9509](https://www.precursorintelligence.com/product/cisco/mds_9509) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9513](https://www.precursorintelligence.com/product/cisco/mds_9513) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9706](https://www.precursorintelligence.com/product/cisco/mds_9706) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9710](https://www.precursorintelligence.com/product/cisco/mds_9710) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Mds 9718](https://www.precursorintelligence.com/product/cisco/mds_9718) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N77-F312ck-26](https://www.precursorintelligence.com/product/cisco/n77-f312ck-26) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N77-F324fq-25](https://www.precursorintelligence.com/product/cisco/n77-f324fq-25) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N77-F348xp-23](https://www.precursorintelligence.com/product/cisco/n77-f348xp-23) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N77-F430cq-36](https://www.precursorintelligence.com/product/cisco/n77-f430cq-36) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N77-M312cq-26l](https://www.precursorintelligence.com/product/cisco/n77-m312cq-26l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N77-M324fq-25l](https://www.precursorintelligence.com/product/cisco/n77-m324fq-25l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N77-M348xp-23l](https://www.precursorintelligence.com/product/cisco/n77-m348xp-23l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-F248xp-25e](https://www.precursorintelligence.com/product/cisco/n7k-f248xp-25e) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-F306ck-25](https://www.precursorintelligence.com/product/cisco/n7k-f306ck-25) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-F312fq-25](https://www.precursorintelligence.com/product/cisco/n7k-f312fq-25) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-M202cf-22l](https://www.precursorintelligence.com/product/cisco/n7k-m202cf-22l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-M206fq-23l](https://www.precursorintelligence.com/product/cisco/n7k-m206fq-23l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-M224xp-23l](https://www.precursorintelligence.com/product/cisco/n7k-m224xp-23l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-M324fq-25l](https://www.precursorintelligence.com/product/cisco/n7k-m324fq-25l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N7k-M348xp-25l](https://www.precursorintelligence.com/product/cisco/n7k-m348xp-25l) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C92160yc-X](https://www.precursorintelligence.com/product/cisco/n9k-c92160yc-x) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C9236c](https://www.precursorintelligence.com/product/cisco/n9k-c9236c) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C9272q](https://www.precursorintelligence.com/product/cisco/n9k-c9272q) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C93180lc-EX](https://www.precursorintelligence.com/product/cisco/n9k-c93180lc-ex) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C93180yc-EX](https://www.precursorintelligence.com/product/cisco/n9k-c93180yc-ex) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C93180yc-Fx](https://www.precursorintelligence.com/product/cisco/n9k-c93180yc-fx) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C9504-Fm-R](https://www.precursorintelligence.com/product/cisco/n9k-c9504-fm-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-C9508-Fm-R](https://www.precursorintelligence.com/product/cisco/n9k-c9508-fm-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-X96136yc-R](https://www.precursorintelligence.com/product/cisco/n9k-x96136yc-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-X9636c-R](https://www.precursorintelligence.com/product/cisco/n9k-x9636c-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-X9636c-Rx](https://www.precursorintelligence.com/product/cisco/n9k-x9636c-rx) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-X9636q-R](https://www.precursorintelligence.com/product/cisco/n9k-x9636q-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-X9732c-EX](https://www.precursorintelligence.com/product/cisco/n9k-x9732c-ex) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [N9k-X9736c-Fx](https://www.precursorintelligence.com/product/cisco/n9k-x9736c-fx) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 3048](https://www.precursorintelligence.com/product/cisco/nexus_3048) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - Nexus 3524-X/xl by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - Nexus 3548-X/xl by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 36180yc-R](https://www.precursorintelligence.com/product/cisco/nexus_36180yc-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 3636c-R](https://www.precursorintelligence.com/product/cisco/nexus_3636c-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5010](https://www.precursorintelligence.com/product/cisco/nexus_5010) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5020](https://www.precursorintelligence.com/product/cisco/nexus_5020) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5548p](https://www.precursorintelligence.com/product/cisco/nexus_5548p) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5548up](https://www.precursorintelligence.com/product/cisco/nexus_5548up) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5596t](https://www.precursorintelligence.com/product/cisco/nexus_5596t) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5596up](https://www.precursorintelligence.com/product/cisco/nexus_5596up) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 56128p](https://www.precursorintelligence.com/product/cisco/nexus_56128p) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5624q](https://www.precursorintelligence.com/product/cisco/nexus_5624q) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5648q](https://www.precursorintelligence.com/product/cisco/nexus_5648q) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5672up](https://www.precursorintelligence.com/product/cisco/nexus_5672up) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5672up-16g](https://www.precursorintelligence.com/product/cisco/nexus_5672up-16g) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 5696q](https://www.precursorintelligence.com/product/cisco/nexus_5696q) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 6001](https://www.precursorintelligence.com/product/cisco/nexus_6001) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 6004](https://www.precursorintelligence.com/product/cisco/nexus_6004) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 7000 Supervisor 1](https://www.precursorintelligence.com/product/cisco/nexus_7000_supervisor_1) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 7000 Supervisor 2](https://www.precursorintelligence.com/product/cisco/nexus_7000_supervisor_2) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 7000 Supervisor 2e](https://www.precursorintelligence.com/product/cisco/nexus_7000_supervisor_2e) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 7700 Supervisor 2e](https://www.precursorintelligence.com/product/cisco/nexus_7700_supervisor_2e) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [Nexus 7700 Supervisor 3e](https://www.precursorintelligence.com/product/cisco/nexus_7700_supervisor_3e) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [UCS 6248up](https://www.precursorintelligence.com/product/cisco/ucs_6248up) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [UCS 6324](https://www.precursorintelligence.com/product/cisco/ucs_6324) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [UCS 6332](https://www.precursorintelligence.com/product/cisco/ucs_6332) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [UCS 6332-16up](https://www.precursorintelligence.com/product/cisco/ucs_6332-16up) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [UCS-6296up](https://www.precursorintelligence.com/product/cisco/ucs-6296up) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [X96136yc-R](https://www.precursorintelligence.com/product/cisco/x96136yc-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [X9636c-R](https://www.precursorintelligence.com/product/cisco/x9636c-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [X9636c-Rx](https://www.precursorintelligence.com/product/cisco/x9636c-rx) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified - [X9636q-R](https://www.precursorintelligence.com/product/cisco/x9636q-r) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Hardware): version not specified ## How do I fix CVE-2019-1965? 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-20190828-nxos-memleak-dos) (Vendor advisory) ## Questions ### What is CVE-2019-1965? CVE-2019-1965 is a high-severity flaw in NX-OS from Cisco, published on 28 August 2019. It can be attacked from anywhere on the internet with an ordinary user account, and nobody has to click anything. If it works, the attacker can take it offline. ### How serious is CVE-2019-1965? It scores 7.7 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2019-1965 is 46 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-2019-1965 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 1.5%. That can change at any time, which is why we keep watching. ### Which versions does CVE-2019-1965 affect? For NX-OS from Cisco: before 7.1(5)n1(1b), before 6.2(22), before 7.0(3)i4(9), before 3.2(3k), 4.0 to before 4.0(2e), 5.2 to before 6.2(29) and 1 more. The record lists 87 products in all, each with its versions, under "Who is affected" on this page. ### How do I fix CVE-2019-1965? 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-2019-1965 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