Cyber Resilience

CVE-2023-20032

Memory Safety in Clamav ≤ 0.103.7

Published
01 March 2023
Modified
21 November 2024
Patch / 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 0.29 98th percentile
Risk Priority 86 floored blend · peak EPSS

Summary

CVE-2023-20032 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Clamav Clamav. 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 2% 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.

CVE-2023-20032 is a heap buffer overflow vulnerability in the HFS+ partition file parser within the ClamAV scanning library, caused by a missing buffer size check. It affects ClamAV versions 1.0.0 and earlier, 0.105.1 and earlier, and 0.103.7 and earlier, and carries a CVSS 3.1 score of 9.8 with associated CWEs 120 and 787.

An unauthenticated remote attacker can exploit the flaw by submitting a specially crafted HFS+ partition file for scanning on an affected system. Successful exploitation grants arbitrary code execution with the privileges of the ClamAV process or triggers a denial-of-service condition by crashing the scanner.

The referenced Cisco Security Advisory describes the vulnerability and directs users to the ClamAV blog for further details on affected releases and remediation steps.

EPSS for this CVE rose from lower values to a peak of 0.1032, indicating increased exploitation interest after public disclosure before receding to the current score of 0.0712.

EU & UK References

Vulnerability Data

On Feb 15, 2023, the following vulnerability in the ClamAV scanning library was disclosed: A vulnerability in the HFS+ partition file parser of ClamAV versions 1.0.0 and earlier, 0.105.1 and earlier, and 0.103.7 and earlier could allow an unauthenticated, remote…

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attacker to execute arbitrary code. This vulnerability is due to a missing buffer size check that may result in a heap buffer overflow write. An attacker could exploit this vulnerability by submitting a crafted HFS+ partition file to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to execute arbitrary code with the privileges of the ClamAV scanning process, or else crash the process, resulting in a denial of service (DoS) condition. For a description of this vulnerability, see the ClamAV blog ["https://blog.clamav.net/"].

CWE(s)

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.
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.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-20213Same product: Cisco Secure Endpoint
CVE-2026-20217Same product: Cisco Secure Endpoint
CVE-2026-20215Same product: Cisco Secure Endpoint
CVE-2026-20244Same product: Cisco Secure Endpoint
CVE-2026-20214Same product: Cisco Secure Endpoint
CVE-2026-20243Same product: Cisco Secure Endpoint
CVE-2023-47091Same product: Stormshield Stormshield Network Security
CVE-2023-43548Shared CWE-120, CWE-787
CVE-2023-7222Shared CWE-120, CWE-787
CVE-2023-3164Shared CWE-120, CWE-787

Affected Assets

cisco
secure endpoint
≤ 1.20.2 · ≤ 1.21.1 · ≤ 7.5.9
cisco
secure endpoint private cloud
≤ 3.6.0
cisco
web security appliance
≤ 12.5.6 · 14.0.0 — 14.0.4-005 · 14.5.0 — 14.5.1-013
clamav
clamav
1.0.0 · ≤ 0.103.7 · 0.104.0 — 0.105.1
stormshield
stormshield network security
3.0.0 — 3.7.35 · 3.8.0 — 3.11.23 · 4.3.0 — 4.3.17

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.2.1

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-120

Platform-independent managed code eliminates the need for unchecked native buffer copies that are the root cause of classic buffer overflows.

addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

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 development practices directly enforce bounds checking and input validation that prevent classic buffer overflows.

ID.RA-01 partial match
prevents

Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.

PR.PS-02 partial match
prevents

Routine patching replaces vulnerable code containing unchecked buffer copies with corrected versions.

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.

prevents

Secure coding directly requires bounds-checked memory operations, addressing the root cause of CWE-120.

finds

Security testing in development and acceptance can detect buffer overflows through fuzzing and static analysis, though it does not prevent them at the source.

prevents

Secure development life cycle mandates processes that can include input validation and bounds checking to prevent buffer overflows.

prevents

Application security requirements can specify input-size validation and safe buffer handling to mitigate classic buffer overflows.

prevents

Secure system architecture and engineering principles promote defensive coding patterns that reduce the likelihood of unchecked buffer copies.

prevents

Change management can enforce review gates that catch unsafe memory operations before deployment.

References