Cyber Resilience

CVE-2026-39938

CriticalRCE

Published: 24 June 2026

Published
24 June 2026
Modified
26 June 2026
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0044 35.0th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-39938 is a critical-severity Path Traversal (CWE-22) vulnerability in Cacti Cacti. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 35.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability details

Cacti is an open source performance and fault management framework. Versions 1.2.30 and prior have unauthenticated LFI through graph_theme and rrdtool IPC serialization hardening. This issue has been resolved in version 1.2.31.

CWE(s)

Related Threats

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.
Why these techniques?

Unauthenticated LFI + command injection (CWE-22/78) in public Cacti web app directly enables remote exploitation of a public-facing application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

cacti
cacti
≤ 1.2.31

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.

addresses: CWE-22 CWE-78

Validates pathnames and filenames to prevent traversal outside intended directories.

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