Raw vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-39469 is a high-severity Code Injection (CWE-94) vulnerability in Papercut Papercut Mf. Its CVSS base score is 7.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Junk Data (T1001.001); ranked in the top 0.8% 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 SI-10 (Information Input Validation) — 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-2023-39469 is a remote code execution vulnerability in PaperCut NG stemming from improper validation of a user-supplied string within the External User Lookup functionality. The flaw permits the string to be used directly for Java code execution, classified under CWE-94, and carries a CVSS 3.1 score of 7.2 reflecting network-accessible attack with high-privilege requirements but full system impact.
An authenticated remote attacker can supply a crafted string to the External User Lookup feature and achieve arbitrary code execution in the context of the SYSTEM account on affected PaperCut NG installations.
Public advisories from PaperCut and Zero Day Initiative detail the issue as ZDI-CAN-21013 and direct administrators to the July 2023 security bulletin for patch and mitigation guidance. The associated EPSS score rose materially from lower values to a peak of 0.6029 on 2025-12-11 before receding to the current 0.1658, indicating a period of heightened exploitation interest after disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-43192
Vulnerability Data
PaperCut NG External User Lookup Code Injection Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of PaperCut NG. Authentication is required to exploit this vulnerability. The specific flaw exists within the External…
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User Lookup functionality. The issue results from the lack of proper validation of a user-supplied string before using it to execute Java code. An attacker can leverage this vulnerability to execute code in the context of SYSTEM. Was ZDI-CAN-21013.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.3.1
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation finds code paths that accept and execute externally influenced strings.
Input validation directly stops untrusted data from being used to construct executable code without neutralization.
Least privilege limits the damage an injected code fragment can perform once executed.
Requiring documented secure development standards and tools enforces use of safe code-generation APIs and escaping.
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's SDLC practices directly target injection flaws via secure coding and testing (mostly), yet as a single broad outcome it leaves many code-generation specifics unaddressed (partial).
PR.DS-10 protects runtime data confidentiality/integrity but has no bearing on neutralizing externally influenced input during code generation, so neither direction shows any preventive effect.
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.