CVE-2026-89259

Status: DeferredCritical (9.3)—

Hugo is a static site generator. From v0.161.0, Hugo executes Node tools under Node's permission model, but TailwindCSS — included in the default security.exec.allow list — requires a highly permissive configuration (--allow-addons, --allow-child-process, --allow-worker). As a result, the restrictions intended by the fix for GHSA-x597-9fr4-5857 could still be bypassed, allowing a Node tool invoked during a build to read and write files outside the project's working directory.

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Affected versions are those after v0.43; the issue was fixed in v0.165.0 by removing tailwindcss from the default security.exec.allow list. Users who do not use TailwindCSS, or who only build trusted sites, are not affected. As a workaround, users can define a restrictive security.exec.allow list in hugo.toml.

CVSS

Version: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Base score: 9.3

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.59%
Percentile among all scored CVEs: 46
Score date: 10/4/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access85 %
Primary impactT1005 Data from Local Systemcollection80 %
Secondary impactT1068 Exploitation for Privilege Escalationprivilege escalation75 %
Secondary impactT1565.001 Stored Data Manipulationimpact80 %

Hugo ejecuta herramientas Node (TailwindCSS) con modelo de permisos insuficiente, permitiendo lectura/escritura fuera del directorio del proyecto. AV:N sin autenticación → T1190. Capacidad de leer/escribir archivos fuera de scope y escalada implícita de privilegios.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Application Isolation and Sandboxing Exploit Protection Update Software Vulnerability Scanning Threat Intelligence Program Restrict File and Directory Permissions

Affected technologies (2)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Gohugo — Hugo^AI Tailwindcss — Tailwindcss^AI

CWEs

CWE-250

References

Raw JSON (NVD)

Show

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      "value": "Hugo is a static site generator. From v0.161.0, Hugo executes Node tools under Node's permission model, but TailwindCSS — included in the default security.exec.allow list — requires a highly permissive configuration (--allow-addons, --allow-child-process, --allow-worker). As a result, the restrictions intended by the fix for GHSA-x597-9fr4-5857 could still be bypassed, allowing a Node tool invoked during a build to read and write files outside the project's working directory. Affected versions are those after v0.43; the issue was fixed in v0.165.0 by removing tailwindcss from the default security.exec.allow list. Users who do not use TailwindCSS, or who only build trusted sites, are not affected. As a workaround, users can define a restrictive security.exec.allow list in hugo.toml."
    }
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  "lastModified": "2026-09-24T20:43:32.537",
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}