rubygem-safemode: Sandboxed code execution vulnerability (CVE-2026-107360)
The rubygem-safemode library contains a sandbox escape vulnerability where compound assignment expressions are not subjected to Jail allow-list validation, allowing authenticated attackers to execute arbitrary no-argument methods.
CVE search metadata
CVE search record: CVE-2026-107360. Severity: critical. CVSS: 9.6. KEV: no. Product: rubygem-safemode. Brief: rubygem-safemode: Sandboxed code execution vulnerability (CVE-2026-107360). Brief link: https://feed.craftedsignal.io/briefs/2026-11-safemode-sandbox-escape-cve-2026-107360/
Triage facts
Revision 1- Applicability
- rubygem-safemode
- Evidence
- Unknown
- Severity
- Critical
- Sources
- 1 public source
- Freshness
- Revision 1Nov 12, 20:47 UTC
- Vulnerabilities
- 1 CVE
- Source quality
- A2Roughly even chance
CVE-2026-107360 is a vulnerability in the rubygem-safemode library where compound assignment expressions within sandboxed code are evaluated without properly mediating method calls through the required Jail allow-list.
Impact
An authenticated attacker who can supply template content can bypass sandbox restrictions. This allows the attacker to invoke arbitrary no-argument methods on objects exposed to the template renderer, potentially leading to unauthorized data disclosure or destructive system operations, such as host deletion.
Recommendation
Audit applications using rubygem-safemode to determine if user-controlled input can influence template rendering.