Cyber Resilience

CVE-2018-8373

Memory Safety in Microsoft Internet Explorer 10 … 9

CISA KEVActive ExploitationEUVD ExploitedMemory Safety
Published
15 August 2018
Modified
28 October 2025
KEV Added
25 March 2022
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:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.54 99th percentile
Risk Priority 82 floored blend · peak EPSS

Summary

CVE-2018-8373 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Microsoft Internet Explorer. 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 1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities 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 remote code execution vulnerability exists in the scripting engine's handling of objects in memory within Internet Explorer, resulting in memory corruption classified under CWE-787. The issue affects Internet Explorer 9, Internet Explorer 10, and Internet Explorer 11, and is distinct from several related scripting engine flaws disclosed around the same time.

An attacker can exploit the flaw over the network without authentication by serving malicious content that triggers the memory corruption when rendered in a vulnerable browser instance. Successful exploitation requires user interaction such as visiting a crafted webpage and can yield full control over confidentiality, integrity, and availability on the target system, consistent with the CVSS 7.5 rating reflecting high attack complexity.

Microsoft published an advisory addressing CVE-2018-8373 along with related security bulletins that practitioners should consult for patch availability and configuration guidance. No information on observed in-the-wild exploitation is provided in the source references.

EU & UK References

Vulnerability Data

A remote code execution vulnerability exists in the way that the scripting engine handles objects in memory in Internet Explorer, aka "Scripting Engine Memory Corruption Vulnerability." This affects Internet Explorer 9, Internet Explorer 11, Internet Explorer 10. This CVE ID…

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is unique from CVE-2018-8353, CVE-2018-8355, CVE-2018-8359, CVE-2018-8371, CVE-2018-8372, CVE-2018-8385, CVE-2018-8389, CVE-2018-8390.

CWE(s)
CWE-787
KEV Date Added
25 March 2022

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 →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
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-2018-8653Same product: Microsoft Internet Explorerboth on KEV
CVE-2018-8174Same product: Microsoft Windows 10 1607both on KEV
CVE-2017-0222Same product: Microsoft Internet Explorerboth on KEV
CVE-2019-1367Same product: Microsoft Internet Explorerboth on KEV
CVE-2020-0968Same product: Microsoft Internet Explorerboth on KEV
CVE-2020-1380Same product: Microsoft Internet Explorerboth on KEV
CVE-2017-0149Same product: Microsoft Internet Explorerboth on KEV
CVE-2020-0878Same product: Microsoft Internet Explorerboth on KEV
CVE-2020-1020Same product: Microsoft Windows 10 1507both on KEV
CVE-2020-1027Same product: Microsoft Windows 10 1507both on KEV

Affected Assets

microsoft
internet explorer
10, 11, 9

Mitigating Controls

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.

SI-16 Memory Protection
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 (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.

ID.RA-01 partial match
prevents

Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.

PR.PS-02 partial match
prevents

Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.

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 and acceptance can detect and prevent out-of-bounds write defects.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates practices that prevent out-of-bounds writes.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify bounds-checking and safe memory handling.

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

Secure architecture and engineering principles reduce the likelihood of buffer overflows.

A.8.28 Secure coding partial match
prevents

Secure coding directly addresses out-of-bounds writes through language choice and coding standards.

A.8.32 Change management partial match
prevents

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

References