Routeros: Improper Link Resolution Before File Access
CVE-2022-34960 is a critical-severity improper link resolution before file access vulnerability in Routeros from MikroTik, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Routeros versions: 7.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.59% chance of exploitation within 30 days, higher than 76% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Routeros you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
Official description
The container package in MikroTik RouterOS 7.4beta4 allows an attacker to create mount points pointing to symbolic links, which resolve to locations on the host device. This allows the attacker to mount any arbitrary file to any location on the host.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Link Resolution Before File Access
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
How developers prevent this class of flaw
- Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.
More Improper Link Resolution Before File Access vulnerabilities (CWE-59)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Technical write-ups (may include proof of concept)
- nns.ee/blog/2022/08/05/routeros-container-rce.htmlExploit, Third Party Advisory
Other vulnerabilities in Routeros
- 7.4 High severity
- 8.8 High severity
- 9.8 Critical severity
- 7.5 High severity
- 7.5 High severity
- 8.8 High severity
Recent Improper Link Resolution Before File Access vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.1 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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