CVE-2026-106559
Backstage is an open framework for building developer portals. Prior to 0.3.25, the @backstage/plugin-scaffolder-backend-module-confluence-to-markdown package is affected by improper input validation in confluence to markdown scaffolder module. Insufficient input validation in the Confluence to Markdown scaffolder module could allow an attacker to influence file write operations during template execution. Exploitation requires a Backstage user to run a template that processes attacker-influenced Confluence content. This issue is fixed in version 0.3.25.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:L
- Base score: 6.3
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.32%
- Percentile among all scored CVEs: 23
- Score date: 10/15/2026
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.
- Exploitation
T1203Exploitation for Client Executionexecution85 % - Primary impact
T1565.002Transmitted Data Manipulationimpact80 % - Secondary impact
T1059Command and Scripting Interpreterexecution65 %
CWE-22 (path traversal) + UI:R + requiere usuario Backstage ejecutando template malicioso = T1203 (ejecución cliente). Impacto: manipulación de archivos durante escritura (T1565.002); posible ejecución de código en template procesado (T1059).
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
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-22, CWE-73
References
Raw JSON (NVD)
Show
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