# What is CVE-2021-3719?

> CVE-2021-3719 is a medium-severity flaw (CVSS 6.7) in Thinkcentre E93 Firmware from Lenovo, published on 12 November 2021. 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 0.3%. If you run an affected version, plan in the vendor’s fix.

Canonical page: https://www.precursorintelligence.com/what-is/cve-2021-3719

## 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:** 23 out of 100 (Low); action: Monitor. Kept up to date as the evidence changes.
- **Severity:** Medium (CVSS 6.7 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:** 0.3% (latest exploit-likelihood forecast)
- **Published:** 12 November 2021
- **Record last updated:** 19 November 2021
- **Main product:** Thinkcentre E93 Firmware from Lenovo
- **Affected products:** 40

## What is CVE-2021-3719? In plain terms

An attacker has to be already on the device with an administrator account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.

### The official description

A potential vulnerability in the SMI callback function that saves and restore boot script tables used for resuming from sleep state in some ThinkCentre and ThinkStation models may allow an attacker with local access and elevated privileges to execute arbitrary code.

### What kind of flaw is it?

- CWE-20: Improper Input Validation

### How an attack on it works

- Where an attacker can be: Already on the device
- How hard it is to pull off: Easy: no special conditions
- Login needed first: An administrator account
- Does someone have to click: No, nobody has to do anything
- What an attacker gets: Can read data, change data and take it offline

Severity vector: `CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`

## Is CVE-2021-3719 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 0.3%. That can change at any time, which is why we keep watching.

Exploit likelihood over the last 7 days: 0.3%, 0.3%, 0.3%, 0.3%, 0.3%, 0.3%, 0.3%.

### Timeline

- 12 November 2021: Published
- 19 November 2021: Record last updated

### How Precursor Intelligence ranks it

CVE-2021-3719 scores **23 out of 100 (Low)**, with the action "Monitor".

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-2021-3719?

The published record lists 40 products. Versions are as published: "before fbktdfa" means every version up to, but not including, fbktdfa.

- [Thinkcentre E93 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_e93_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- [Thinkcentre E93](https://www.precursorintelligence.com/product/lenovo/thinkcentre_e93) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M4500q](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m4500q) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M4500q Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m4500q_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fhkt86a
- [Thinkcentre M600](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m600) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M600 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m600_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before m00kt65a
- Thinkcentre M6500t/s by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- Thinkcentre M6500t/s Firmware by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- [Thinkcentre M700 Tiny](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m700_tiny) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M700 Tiny Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m700_tiny_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fwktb9a
- [Thinkcentre M73](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m73) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M73 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m73_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fhkt86a
- [Thinkcentre M73p](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m73p) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M73p Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m73p_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- [Thinkcentre M800](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m800) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M800 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m800_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fwktb9a
- [Thinkcentre M818z](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m818z) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M818z Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m818z_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before m1ekt23a
- [Thinkcentre M83](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m83) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M83 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m83_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- Thinkcentre M8500t/s by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- Thinkcentre M8500t/s Firmware by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- [Thinkcentre M900](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m900) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M900 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m900_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fwktb9a
- [Thinkcentre M900x](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m900x) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M900x Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m900x_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fwktb9a
- [Thinkcentre M93](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m93) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M93 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m93_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- [Thinkcentre M93p](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m93p) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre M93p Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_m93p_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- [Thinkcentre X1](https://www.precursorintelligence.com/product/lenovo/thinkcentre_x1) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkcentre X1 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkcentre_x1_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before m0hkt50a
- [Thinkstation P300](https://www.precursorintelligence.com/product/lenovo/thinkstation_p300) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkstation P300 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkstation_p300_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fbktdfa
- [Thinkstation P500](https://www.precursorintelligence.com/product/lenovo/thinkstation_p500) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkstation P500 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkstation_p500_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before a4ktaba
- [Thinkstation P700](https://www.precursorintelligence.com/product/lenovo/thinkstation_p700) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkstation P700 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkstation_p700_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before a5ktaba
- [Thinkstation P900](https://www.precursorintelligence.com/product/lenovo/thinkstation_p900) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkstation P900 Firmware](https://www.precursorintelligence.com/product/lenovo/thinkstation_p900_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before a6ktaba

## How do I fix CVE-2021-3719?

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

- [support.lenovo.com](https://support.lenovo.com/us/en/product_security/LEN-67440) (Vendor advisory)

## Questions

### What is CVE-2021-3719?

CVE-2021-3719 is a medium-severity flaw in Thinkcentre E93 Firmware from Lenovo, published on 12 November 2021. An attacker has to be already on the device with an administrator account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.

### How serious is CVE-2021-3719?

It scores 6.7 out of 10 on the CVSS severity scale, which is medium. Our risk score for CVE-2021-3719 is 23 out of 100, which is Low. Its action is "Monitor". No sign of exploitation and a low forecast. Patch it in your normal update cycle.

### Is CVE-2021-3719 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 0.3%. That can change at any time, which is why we keep watching.

### Which versions does CVE-2021-3719 affect?

For Thinkcentre E93 Firmware from Lenovo: before fbktdfa. The record lists 40 products in all, each with its versions, under "Who is affected" on this page.

### How do I fix CVE-2021-3719?

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-2021-3719 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