Cyber Resilience

CVE-2023-24021

Trustwave Modsecurity ≤ 2.9.7

Published
20 January 2023
Modified
02 April 2025
Patch / advisory
View advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS Score 0.0091 57th percentile
Risk Priority 59 floored blend · peak EPSS

Summary

CVE-2023-24021 is a high-severity Improper Null Termination (CWE-170) vulnerability in Trustwave Modsecurity. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 43% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

Incorrect handling of '\0' bytes in file uploads in ModSecurity before 2.9.7 may allow for Web Application Firewall bypasses and buffer over-reads on the Web Application Firewall when executing rules that read the FILES_TMP_CONTENT collection.

CWE(s)
NVD-CWE-OtherCWE-170

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 →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
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-2024-46292Same product: Trustwave Modsecurity
CVE-2024-26689Same product: Debian Debian Linux
CVE-2023-3609Same product: Debian Debian Linux
CVE-2025-39864Same product: Debian Debian Linux
CVE-2025-37885Same product: Debian Debian Linux
CVE-2025-38578Same product: Debian Debian Linux
CVE-2023-42464Same product: Debian Debian Linux
CVE-2025-38346Same product: Debian Debian Linux
CVE-2025-38377Same product: Debian Debian Linux
CVE-2025-38471Same product: Debian Debian Linux

Affected Assets

trustwave
modsecurity
≤ 2.9.7
debian
debian linux
10.0

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 enforce correct string/array termination via coding standards, reviews, and static analysis.

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 missing or incorrect null terminators before release.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates input validation and string handling rules that prevent missing null terminators.

A.8.26 Application security requirements partial match
prevents

Application security requirements can explicitly call for proper string termination and buffer handling.

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

Secure architecture principles include defensive coding practices that address buffer and string termination issues.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly require correct null termination of strings and arrays.

References