Cyber Resilience

CVE-2023-5746

Synology Bc500 Firmware ≤ 1.0.5-0185

Published
25 October 2023
Modified
21 November 2024
Patch / advisory
View advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.017 75th percentile
Risk Priority 78 floored blend · peak EPSS

Summary

CVE-2023-5746 is a critical-severity Use of Externally-Controlled Format String (CWE-134) vulnerability in Synology Bc500 Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 25% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A format string vulnerability exists in the CGI component of Synology Camera Firmware versions prior to 1.0.5-0185, affecting the BC500 and TC500 camera models. Tracked as CVE-2023-5746 and assigned CWE-134, the flaw stems from the use of externally controlled format strings and carries a CVSS 3.1 score of 9.8.

Unauthenticated remote attackers can exploit the issue over the network with no user interaction required, enabling arbitrary code execution that fully compromises confidentiality, integrity, and availability of the affected devices.

The official Synology advisory Synology_SA_23_11 recommends updating the firmware to version 1.0.5-0185 or later to address the vulnerability. The associated EPSS score has remained flat at 0.0589 with no material increase observed since disclosure.

EU & UK References

Vulnerability Data

A vulnerability regarding use of externally-controlled format string is found in the cgi component. This allows remote attackers to execute arbitrary code via unspecified vectors. The following models with Synology Camera Firmware versions before 1.0.5-0185 may be affected: BC500 and…

more

TC500.

CWE(s)
CWE-134

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-39349Same product: Synology Bc500
CVE-2024-5463Same product: Synology Bc500
CVE-2023-47803Same product: Synology Bc500
CVE-2024-39352Same product: Synology Bc500
CVE-2024-39351Same product: Synology Bc500
CVE-2023-47802Same product: Synology Bc500
CVE-2024-39350Same product: Synology Bc500
CVE-2024-11131Same product: Synology Bc500
CVE-2023-5748Same product class: NAS / storage appliance
CVE-2025-12686Same product class: NAS / storage appliance

Affected Assets

synology
bc500 firmware
≤ 1.0.5-0185
synology
tc500 firmware
≤ 1.0.5-0185

Mitigating Controls

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.PS-06 mostly match
prevents

Secure SDLC practices directly prevent external format strings via code review, static analysis, and safe APIs.

ID.RA-01 partial match
prevents

Vulnerability identification can discover existing format-string flaws but does not prevent their introduction.

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.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development can detect format-string vulnerabilities before release.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates input validation and safe API usage that can prevent externally-controlled format strings.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify safe formatting functions and ban uncontrolled format strings.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles discourage dangerous string-handling patterns that lead to format-string issues.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly forbid the use of untrusted format strings and prescribe safe alternatives.

References