Cyber Resilience

CVE-2023-48257

Auth Bypass in Bosch Nexo-Os 1000 – 1500-sp2

Auth Bypass
Published
10 January 2024
Modified
21 November 2024
Patch / advisory
View advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0054 43th percentile
Risk Priority 58 floored blend · peak EPSS

Summary

CVE-2023-48257 is a high-severity Use of Weak Credentials (CWE-1391) vulnerability in Bosch Nexo-Os. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Default Accounts (T1078.001); ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to IA-2 (Identification and Authentication (Organizational Users)) and IA-3 (Device Identification and Authentication) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A07:2025 Authentication Failures

EU & UK References

Vulnerability Data

The vulnerability allows a remote attacker to access sensitive data inside exported packages or obtain up to Remote Code Execution (RCE) with root privileges on the device. The vulnerability can be exploited directly by authenticated users, via crafted HTTP requests,…

more

or indirectly by unauthenticated users, by accessing already-exported backup packages, or crafting an import package and inducing an authenticated victim into sending the HTTP upload request.

CWE(s)
CWE-1391CWE-287

Related Threats

MITRE ATT&CK Enterprise Techniques

T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
attack.mitre.org →
T1110 Brute Force Credential Access
Adversaries may use brute force techniques to gain access to accounts when passwords are unknown or when password hashes are obtained.
attack.mitre.org →
T1110.001 Password Guessing Credential Access
Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts.
attack.mitre.org →
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
attack.mitre.org →
T1110.002 Password Cracking Credential Access
Adversaries may use password cracking to attempt to recover usable credentials, such as plaintext passwords, when credential material such as password hashes are obtained.
attack.mitre.org →
T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-48256Same product: Bosch Nexo-Os
CVE-2023-48254Same product: Bosch Nexo-Os
CVE-2023-48247Same product: Bosch Nexo-Os
CVE-2023-48248Same product: Bosch Nexo-Os
CVE-2023-48251Same product: Bosch Nexo-Os
CVE-2023-48250Same product: Bosch Nexo-Os
CVE-2023-48245Same product: Bosch Nexo-Os
CVE-2023-48255Same product: Bosch Nexo-Os
CVE-2023-48244Same product: Bosch Nexo-Os
CVE-2023-48249Same product: Bosch Nexo-Os

Affected Assets

bosch
nexo-os
1000 — 1500-sp2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 15 hardening rules · 5 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.2.2
  • V6.3.1
  • V6.3.2
  • V6.4.2

Mitigating Controls (NIST 800-53 r5) AI

IA-2 Identification and Authentication (Organizational Users) good match

Mandates unique identification and authentication of organizational users before access, directly stopping improper authentication.

IA-3 Device Identification and Authentication good match

Requires unique identification and authentication of devices before establishing connections, preventing unauthenticated device claims.

IA-5 Authenticator Management good match

IA-5 directly requires management of authenticator strength, distribution, and replacement, stopping default or guessable credentials from being introduced or used.

IA-8 Identification and Authentication (Non-organizational Users) good match

Mandates unique identification and authentication of non-organizational users, directly addressing the weakness for external actors.

AC-3 Access Enforcement partial match

Enforces access only after approved authorizations, which presupposes correct authentication has occurred.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-01 mostly match
prevents

PR.AA-01's credential issuance and key-management processes directly block most weak/default credential usage, yet leave hard-coded or product-design instances of CWE-1391 only partially addressed.

PR.AA-03 mostly match
prevents

Password-strength policies in PR.AA-03 directly block weak authenticators, but the control leaves hard-coded/default credentials largely unaddressed.

PR.AA-04 mostly match
prevents

PR.AA-04 directly enables verification of identity assertions (mostly preventing CWE-287 in that scope) yet leaves many other authentication failure modes unaddressed (only partial prevention overall).

PR.PS-01 mostly match
prevents

Hardened baselines and default-setting reviews directly block default/hard-coded creds (mostly), yet leave algorithmic guessing, reuse, and non-config sources of weak credentials untouched (partial).

PR.AA-02 partial match
prevents

PR.AA-02 ensures valid enrollment and unique credential binding, which reduces some improper-auth risks at issuance time but leaves runtime claim verification untouched, so each direction only partially addresses the other.

PR.AT-01 partial match
prevents

Training raises password-hygiene awareness and can therefore reduce some weak-credential mistakes, yet supplies no enforcement mechanism and leaves the dominant technical sources of CWE-1391 untouched.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.17 Authentication information full match
degrades

Directly requires secure generation, distribution and storage of authentication credentials, eliminating default/hard-coded weak passwords.

A.8.5 Secure authentication full match
degrades

Mandates secure authentication mechanisms that preclude use of weak or default credentials.

A.8.28 Secure coding mostly match
prevents

Secure-coding rules can prohibit hard-coded passwords, yet coverage depends on specific coding standards adopted.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can discover weak credentials, but does not guarantee they are prevented by design.

A.8.9 Configuration management mostly match
prevents

Enforces secure baseline configurations that should remove default credentials, yet does not guarantee credential strength.

A.5.16 Identity management partial match
prevents

Mandating segregated approval and oversight for non-human identities reduces the chance that weak or orphaned credentials can be exploited for unauthorized authentication.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (3 rules)
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-1391, CWE-287
  • V-248667 OL 8 must configure the use of the pam_faillock.so module in the /etc/pam.d/system-auth file. prevents CWE-1391
  • V-248668 OL 8 must configure the use of the pam_faillock.so module in the /etc/pam.d/password-auth file. prevents CWE-1391
RHEL 7 (3 rules)
  • V-204425 The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using an empty password. prevents CWE-287
  • V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-1391, CWE-287
  • V-204424 The Red Hat Enterprise Linux operating system must not allow accounts configured with blank or null passwords. prevents CWE-287
RHEL 8 (2 rules)
  • V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-287
  • V-244533 RHEL 8 must configure the use of the pam_faillock.so module in the /etc/pam.d/system-auth file. prevents CWE-1391
Ubuntu 22.04 (1 rule)
  • V-260470 Ubuntu 22.04 LTS, when booted, must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
Ubuntu 24.04 (2 rules)
  • V-270675 Ubuntu 24.04 LTS when booted must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
  • V-270714 Ubuntu 24.04 LTS must not allow accounts configured in Pluggable Authentication Modules (PAM) with blank or null passwords. prevents CWE-287

References