[NEW] [high] Ruby on Rails: Vulnerability allows information disclosure

highpublic exploitCVE-2026-66066

A remote, anonymous attacker can exploit a vulnerability in Ruby on Rails to disclose information, which may lead to remote code execution or lateral movement.

CSIRTS triage

vendor: Ruby on Rails product: Ruby on Rails Information disclosure Remote code execution

What: A vulnerability allows information disclosure, which may lead to remote code execution or lateral movement.
Who is affected: Remote, anonymous attackers targeting Ruby on Rails deployments.
Urgency: Remediation is urgent due to the high severity and potential for exploitation.
Action: Update to the latest version of Ruby on Rails to mitigate the vulnerability.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: CERT-Bund (BSI) Security Advisories (DE · national-cert · site)
Severity: high
Published: 2026-07-31
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2574

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Moderate exploitation riskCVE-2026-660661.7% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 75% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-66066	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

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