Cyber Resilience

CVE-2026-43986

CriticalUpdated

Published: 04 June 2026

Published
04 June 2026
Modified
17 June 2026
KEV Added
—
Patch
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CVSS Score v3.1 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
EPSS Score 0.0026 17.6th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-43986 is a critical-severity SSRF (CWE-918) vulnerability. Its CVSS base score is 9.9 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 17.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability details

Tautulli is a Python based monitoring and tracking tool for Plex Media Server. Versions prior to 2.17.1 expose a public `/image/<hash>` route that resolves attacker-controlled entries from `image_hash_lookup` and replays them through the same server-side image fetch logic used by…

more

authenticated image proxying. A low-privilege guest user can seed a malicious external image URL into this lookup table and then trigger server-side fetches through a fully unauthenticated endpoint. This turns an authenticated SSRF primitive into a persistent unauthenticated SSRF gadget. Once the malicious hash entry exists, any external user can request `/image/<hash>.png` and cause the PMS or Tautulli host to fetch an arbitrary attacker-chosen URL. Version 2.17.1 patches the issue.

CWE(s)
CWE-918

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.
attack.mitre.org →
Why these techniques?

Direct unauthenticated SSRF in public-facing Tautulli web endpoint (CWE-918) enables exploitation of a public-facing application.

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

Affected Assets

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.

CA-8 Penetration Testing
addresses: CWE-918

Penetration testing attempts server-side requests to internal resources, identifying SSRF weaknesses for remediation.

SC-7 Boundary Protection
addresses: CWE-918

Outbound connections to external resources can be monitored and limited at the boundary, reducing SSRF impact.

SI-10 Information Input Validation
addresses: CWE-918

Validates server-side URLs and resource references to block SSRF attempts.

SI-4 System Monitoring
addresses: CWE-918

Detects server-side request forgery through monitoring of unexpected outbound connections.

References