cnMaestro: Improper Limitation of a Pathname to a Restricted Directory
CVE-2022-1359 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in cnMaestro from Cambium Networks, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 3.0.3-r32, 2.4.2-r29, 3.0.0-r34 as the first without the flaw, so updating cnMaestro to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.98% chance of exploitation within 30 days, higher than 63% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update cnMaestro to 3.0.3-r32 or 2.4.2-r29 or 3.0.0-r34, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Cambium Networks | cnMaestro | before 3.0.3-r32; before 2.4.2-r29; before 3.0.0-r34 | 3.0.3-r32, 2.4.2-r29, 3.0.0-r34 |
Version data comes from the organisation that assigned the CVE. 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
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 5.7 | Medium | CNA (hq.dhs.gov) |
| CVSS 3.1 | 7.5 | High | NVD |
| CVSS 2.0 | 5.0 | Medium | NVD |
Official description
The affected On-Premise cnMaestro is vulnerable to an arbitrary file-write through improper limitation of a pathname to a restricted directory inside a specific route. If an attacker supplied path traversal charters (../) as part of a filename, the server will save the file where the attacker chooses. This could allow an attacker to write any data to any file in the server.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
How developers prevent this class of flaw
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- cisa.gov/uscert/ics/advisories/icsa-22-132-04Third Party Advisory, US Government Resource
Other vulnerabilities in cnMaestro
- 7.3 High severity
- 7.5 High severity
- 9.8 Critical severity
- 7.5 High severity
- 9.8 Critical severity
- 7.8 High severity
Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities
- 9.8 Critical severity
- 9.1 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.5 High severity
RARLAB UnRAR Directory Traversal Exploited
- 8.8 High severity
Spotted an error? Tell us.