CVE-2018-18556
A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows...
A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows operator users to execute the pppd binary with elevated (sudo) permissions. Certain input parameters are not properly validated. A malicious operator user can run the binary with elevated permissions and leverage its improper input validation condition to spawn an attacker-controlled shell with root privileges.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows operator users to execute the pppd binary with elevated (sudo) permissions. Certain input parameters are not properly validated. A malicious operator user can run the binary with elevated permissions and leverage its improper input validation condition to spawn an attacker-controlled shell with root privileges.
- Record
CVE-2018-18556- CVSS 3.1
- 9.9 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - CVSS 2.0
- 9.0 High
AV:N/AC:L/Au:S/C:C/I:C/A:C - Updated
- 2026-11-02
CVE List No score
A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows operator users to execute the pppd binary with elevated (sudo) permissions. Certain input parameters are not properly validated. A malicious operator user can run the binary with elevated permissions and leverage its improper input validation condition to spawn an attacker-controlled shell with root privileges.
- Record
CVE-2018-18556- Updated
- 2026-11-02
EUVDEUVD-2018-10276 No score
A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows operator users to execute the pppd binary with elevated (sudo) permissions. Certain input parameters are not properly validated. A malicious operator user can run the binary with elevated permissions and leverage its improper input validation condition to spawn an attacker-controlled shell with root privileges.
- Record
EUVD-2018-10276- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-8jmm-6g59-87gc
A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows...
A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows operator users to execute the pppd binary with elevated (sudo) permissions. Certain input parameters are not properly validated. A malicious operator user can run the binary with elevated permissions and leverage its improper input validation condition to spawn an attacker-controlled shell with root privileges.
- Record
GHSA-8jmm-6g59-87gc- CVSS 3.0
- 9.9 Critical
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Metasploit | VyOS restricted-shell Escape and Privilege Escalation | 2018-11-05 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, Metasploit, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-18556 is a critical vulnerability (CVSS 9.9) in Vyos, published December 17, 2018. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 15.4%, the 96th percentile. No source names a fixed version.
References
blog.vyos.io/the-operator-level-is-proved-insecure-and-will-be-removed-in-the-next-releases
blog.mirch.io/2018/11/05/cve-2018-18556-vyos-privilege-escalation-via-sudo-pppd-for-operator-users
packetstormsecurity.com/files/159234/VyOS-restricted-shell-Escape-Privilege-Escalation.html
nvd.nist.gov/vuln/detail/CVE-2018-18556
github.com/advisories/GHSA-8jmm-6g59-87gc