CVE-2018-18555
CVE-2018-18555 is a critical-severity vulnerability in Vyos with a CVSS 3.x base score of 9.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.
Key facts
- Severity: Critical (CVSS 3.x base score 9.9)
- CVSS v2: 9.0
- EPSS exploit prediction: 2% (75th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Vyos
- Published:
- Last modified:
Description
A sandbox escape issue was discovered in VyOS 1.1.8. It provides a restricted management shell for operator users to administer the device. By issuing various shell special characters with certain commands, an authenticated operator user can break out of the management shell and gain access to the underlying Linux shell. The user can then run arbitrary operating system commands with the privileges afforded by their account.
Frequently asked questions
- What is CVE-2018-18555?
- A sandbox escape issue was discovered in VyOS 1.1.8. It provides a restricted management shell for operator users to administer the device. By issuing various shell special characters with certain commands, an authenticated operator user can break out of the management shell and gain access to the underlying Linux shell. The user can then run arbitrary operating system commands with the privileges afforded by their account.
- How severe is CVE-2018-18555?
- CVE-2018-18555 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2018-18555 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2018-18555?
- CVE-2018-18555 affects Vyos. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2018-18555?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2018-18555 published?
- CVE-2018-18555 was published on 2018-12-17 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:vyos:vyos:1.1.8:*:*:*:*:*:*:*
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