CVE-2018-18556
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 15.4% chance of exploitation in the next 30 days (EPSS). Higher than most.
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 15.4% in the next 30 days (EPSS).
- Severity: 9.9 CRITICAL (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 15.4% · EPSS, next 30 days
- Record status
- Modified
Affected
- Vyos 1.1.8
Attack profile CVSS 3.1 · 9.9
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2018-18556.md and follow it. Check whether this project is affected by CVE-2018-18556. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://blog.vyos.io/the-operator-level-is-proved-insecure-and-will-be-removed-in-the-next-releases
- https://blog.vyos.io/the-operator-level-is-proved-insecure-and-will-be-removed-in-the-next-releases
References
- http://packetstormsecurity.com/files/159234/VyOS-restricted-shell-Escape-Privilege-Escalation.html
- https://blog.mirch.io/2018/11/05/cve-2018-18556-vyos-privilege-escalation-via-sudo-pppd-for-operator-users/
- https://blog.vyos.io/the-operator-level-is-proved-insecure-and-will-be-removed-in-the-next-releases
- http://packetstormsecurity.com/files/159234/VyOS-restricted-shell-Escape-Privilege-Escalation.html
- https://blog.mirch.io/2018/11/05/cve-2018-18556-vyos-privilege-escalation-via-sudo-pppd-for-operator-users/
- https://blog.vyos.io/the-operator-level-is-proved-insecure-and-will-be-removed-in-the-next-releases