CVE-2021-23850

Code execution via recovery-mode telnet stack overflow

Published Mar 30, 2022 · Updated Sep 17, 2024

Stack-based buffer overflow in Bosch CPP Firmware allows physically proximate attackers to crash recovery-mode telnet or execute code. Bosch identifies a crafted TCP/IP packet as the trigger but has not disclosed the telnet parsing routine or the precise operation that overruns the stack. Recovery mode must first be booted through physical access or an administrator-only command; exploitation can crash the recovery application or run code on the camera.

CVSS severity6.8
Medium
EPSS probability1.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in Bosch CPP Firmware allows physically proximate attackers to crash recovery-mode telnet or execute code. Bosch identifies a crafted TCP/IP packet as the trigger but has not disclosed the telnet parsing routine or the precise operation that overruns the stack. Recovery mode must first be booted through physical access or an administrator-only command; exploitation can crash the recovery application or run code on the camera.

The record

CVE
CVE-2021-23850
Published
Mar 30, 2022
Updated
Sep 17, 2024
Vendor
Bosch Security Systems B.V.
Product
CPP Firmware
Classifications
CWE-121, T1210
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 30, 2022CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=all

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

Bosch Security Systems B.V. · CPP Firmwareversion=all

Published CVSS scores

6.8Bosch PSIRTCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow
T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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