# What is CVE-2023-4028?

> CVE-2023-4028 is a medium-severity flaw (CVSS 6.7) in 13w Yoga Firmware from Lenovo, published on 17 August 2023. 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 0.2%. If you run an affected version, plan in the vendor’s fix.

Canonical page: https://www.precursorintelligence.com/what-is/cve-2023-4028

## 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:** 0.2% (latest exploit-likelihood forecast)
- **Published:** 17 August 2023
- **Record last updated:** 24 August 2023
- **Main product:** 13w Yoga Firmware from Lenovo
- **Affected products:** 58

## What is CVE-2023-4028? 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 buffer overflow has been identified in the SystemUserMasterHddPwdDxe driver in some Lenovo Notebook products which may allow an attacker with local access and elevated privileges to execute arbitrary code.

### What kind of flaw is it?

- CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

### 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-2023-4028 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 0.2%. That can change at any time, which is why we keep watching.

Exploit likelihood over the last 7 days: 0.2%, 0.2%, 0.2%, 0.2%, 0.2%, 0.2%, 0.2%.

### Timeline

- 17 August 2023: Published
- 24 August 2023: Record last updated

### How Precursor Intelligence ranks it

CVE-2023-4028 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-2023-4028?

The published record lists 58 products. Versions are as published: "before jacn38ww" means every version up to, but not including, jacn38ww.

- [13w Yoga Firmware](https://www.precursorintelligence.com/product/lenovo/13w_yoga_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before jacn38ww
- [13w Yoga](https://www.precursorintelligence.com/product/lenovo/13w_yoga) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [13w Yoga Gen 2](https://www.precursorintelligence.com/product/lenovo/13w_yoga_gen_2) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [13w Yoga Gen 2 Firmware](https://www.precursorintelligence.com/product/lenovo/13w_yoga_gen_2_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before kbcn20ww
- [Flex 5-14alc05](https://www.precursorintelligence.com/product/lenovo/flex_5-14alc05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 5-14alc05 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_5-14alc05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before gjcn32ww
- [Flex 5-14are05](https://www.precursorintelligence.com/product/lenovo/flex_5-14are05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 5-14are05 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_5-14are05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before eecn43ww
- [Flex 5-14iil05](https://www.precursorintelligence.com/product/lenovo/flex_5-14iil05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 5-14iil05 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_5-14iil05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before eccn45ww
- [Flex 5-14itl05](https://www.precursorintelligence.com/product/lenovo/flex_5-14itl05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 5-14itl05 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_5-14itl05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fxcn44ww
- [Flex 5-15alc05](https://www.precursorintelligence.com/product/lenovo/flex_5-15alc05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 5-15alc05 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_5-15alc05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before gjcn32ww
- [Flex 5-15iil05](https://www.precursorintelligence.com/product/lenovo/flex_5-15iil05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 5-15iil05 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_5-15iil05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before eccn45ww
- [Flex 5-15itl05](https://www.precursorintelligence.com/product/lenovo/flex_5-15itl05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 5-15itl05 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_5-15itl05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fxcn44ww
- [Flex 7 14iru8](https://www.precursorintelligence.com/product/lenovo/flex_7_14iru8) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Flex 7 14iru8 Firmware](https://www.precursorintelligence.com/product/lenovo/flex_7_14iru8_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before l6cn20ww
- [Ideapad 1-11ada05](https://www.precursorintelligence.com/product/lenovo/ideapad_1-11ada05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad 1-11ada05 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_1-11ada05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fqcn29ww
- [Ideapad 1-11igl05](https://www.precursorintelligence.com/product/lenovo/ideapad_1-11igl05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad 1-11igl05 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_1-11igl05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before dwcn28ww
- [Ideapad 1-14ada05](https://www.precursorintelligence.com/product/lenovo/ideapad_1-14ada05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad 1-14ada05 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_1-14ada05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fqcn29ww
- [Ideapad 1-14igl05](https://www.precursorintelligence.com/product/lenovo/ideapad_1-14igl05) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad 1-14igl05 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_1-14igl05_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before dwcn28ww
- [Ideapad Flex 5 14abr8](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14abr8) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 14abr8 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14abr8_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before l7cn17ww
- [Ideapad Flex 5 14alc7](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14alc7) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 14alc7 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14alc7_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before jccn35ww
- [Ideapad Flex 5 14iau7](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14iau7) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 14iau7 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14iau7_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before j7cn44ww
- [Ideapad Flex 5 14iru8](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14iru8) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 14iru8 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_14iru8_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before l6cn20ww
- [Ideapad Flex 5 16abr8](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16abr8) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 16abr8 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16abr8_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before l7cn17ww
- [Ideapad Flex 5 16alc7](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16alc7) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 16alc7 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16alc7_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before jccn35ww
- [Ideapad Flex 5 16iau7](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16iau7) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 16iau7 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16iau7_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before j7cn44ww
- [Ideapad Flex 5 16iru8](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16iru8) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Ideapad Flex 5 16iru8 Firmware](https://www.precursorintelligence.com/product/lenovo/ideapad_flex_5_16iru8_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before l6cn20ww
- [Thinkbook 13s G2 Are](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g2_are) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkbook 13s G2 Are Firmware](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g2_are_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before fvcn28ww
- [Thinkbook 13s G2 Itl](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g2_itl) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkbook 13s G2 Itl Firmware](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g2_itl_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before f9cn57ww
- [Thinkbook 13s G3 Acn](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g3_acn) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkbook 13s G3 Acn Firmware](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g3_acn_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before gmcn35ww
- [Thinkbook 13s G4 Iap](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g4_iap) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkbook 13s G4 Iap Firmware](https://www.precursorintelligence.com/product/lenovo/thinkbook_13s_g4_iap_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before hwcn49ww
- [Thinkbook 13x G2 Iap](https://www.precursorintelligence.com/product/lenovo/thinkbook_13x_g2_iap) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkbook 13x G2 Iap Firmware](https://www.precursorintelligence.com/product/lenovo/thinkbook_13x_g2_iap_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before hxcn54ww
- [Thinkbook 14s G2 Itl](https://www.precursorintelligence.com/product/lenovo/thinkbook_14s_g2_itl) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Thinkbook 14s G2 Itl Firmware](https://www.precursorintelligence.com/product/lenovo/thinkbook_14s_g2_itl_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before f9cn57ww
- [Yoga 9-15imh5](https://www.precursorintelligence.com/product/lenovo/yoga_9-15imh5) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Hardware): version not specified
- [Yoga 9-15imh5 Firmware](https://www.precursorintelligence.com/product/lenovo/yoga_9-15imh5_firmware) by [Lenovo](https://www.precursorintelligence.com/vendors/lenovo) (Operating system): before epcn32ww

## How do I fix CVE-2023-4028?

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-134879) (Vendor advisory)

## Questions

### What is CVE-2023-4028?

CVE-2023-4028 is a medium-severity flaw in 13w Yoga Firmware from Lenovo, published on 17 August 2023. 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-2023-4028?

It scores 6.7 out of 10 on the CVSS severity scale, which is medium. Our risk score for CVE-2023-4028 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-2023-4028 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 0.2%. That can change at any time, which is why we keep watching.

### Which versions does CVE-2023-4028 affect?

For 13w Yoga Firmware from Lenovo: before jacn38ww. The record lists 58 products in all, each with its versions, under "Who is affected" on this page.

### How do I fix CVE-2023-4028?

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-2023-4028 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