Cyber Posture

CVE-2026-8450

CriticalRCE
Microsoft: not affectedMSmacOS: not affectedMacLinux: not affectedLnxMobile: not affectedMobNetwork: not affectedNetApplication: not affectedAppOther: affectedOth

Published: 27 May 2026

Published
27 May 2026
Modified
27 May 2026
KEV Added
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Patch
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CVSS Score 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0022 44.1th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-8450 is a critical-severity External Control of File Name or Path (CWE-73) vulnerability. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 44.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique.
Deeper analysisAI

Automated synthesis unavailable for this CVE.

Vulnerability

HTTP::Daemon versions before 6.17 for Perl allow OS command injection via send_file(). send_file() opens its string argument with Perl's 2-arg open(). The 2-arg form interprets magic prefixes: '| cmd' and 'cmd |' open a pipe to a subprocess, '> path'…

more

and '>> path' open the path for write or append. Untrusted input passed to send_file() can run OS commands at the daemon process UID. The read-pipe form ('cmd |') also leaks subprocess stdout into the HTTP response body. The write-mode forms can create or truncate files at attacker chosen paths.

CWE(s)
CWE-73CWE-78
OWASP Top 10 Web 2025
A05:2025A06:2025

EU & UK References

Regulatory context (EU CRA / NIS2 / DORA / UK NIS Regulations)

EU Cyber Resilience Act — coordinated disclosure

Critical and high-severity vulnerabilities in products with digital elements may trigger coordinated-disclosure obligations under the EU Cyber Resilience Act (CRA, Regulation 2024/2847). Manufacturers placing products on the EU market must notify ENISA and the relevant CSIRTs without undue delay once active exploitation is known.

Affected Products

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Daemon
inferred from references and description; NVD did not file a CPE for this CVE

Threat picture

MITRE ATT&CK Enterprise TechniquesAI

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 →
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
attack.mitre.org →
Why these techniques?

Direct OS command injection in public-facing HTTP::Daemon Perl module enables remote exploitation of the server (T1190) and arbitrary Unix shell command execution (T1059.004).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

Defense & controls

Likely Mitigating ControlsAI

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-10 Information Input Validation
addresses: CWE-73 CWE-78

Rejects externally supplied file or resource identifiers that fail validity checks.

SC-27 Platform-independent Applications
addresses: CWE-78

Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.

References