Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:NCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-42114 is a medium-severity Out-of-bounds Read (CWE-125) vulnerability in Exim Exim. Its CVSS base score is 5.3 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.
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-2023-42114 is an out-of-bounds read vulnerability in Exim that permits information disclosure. The flaw resides in the handling of NTLM challenge requests, where insufficient validation of user-supplied data allows a read past the end of an allocated structure. It affects Exim installations and carries a CVSS score of 5.3 under CWE-125.
Remote attackers can exploit the issue without authentication or user interaction by sending crafted NTLM challenge requests, resulting in disclosure of sensitive information in the context of the Exim service account.
Advisories from the Zero Day Initiative, originally tracked as ZDI-CAN-17433, and the Debian LTS announcement detail the vulnerability and direct administrators to apply available updates for affected Exim versions. The EPSS score has remained flat at 0.1389 with no material increase since disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-46573
Vulnerability Data
Exim NTLM Challenge Out-Of-Bounds Read Information Disclosure Vulnerability. This vulnerability allows remote attackers to disclose sensitive information on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of NTLM challenge…
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requests. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated data structure. An attacker can leverage this vulnerability to disclose information in the context of the service account. . Was ZDI-CAN-17433.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation directly finds out-of-bounds read flaws through static analysis, fuzzing, and dynamic bounds checks.
Secure engineering principles require bounds checking and memory-safe constructs that stop out-of-bounds reads from being introduced.
Process isolation confines the effects of an out-of-bounds read to the compromised process.
Input validation rejects malformed indices or lengths that would otherwise cause reads outside buffer bounds.
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.
Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.
Routine patching replaces vulnerable code containing out-of-bounds read flaws.
Secure-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.
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.