TN-5900 Series: Improper Authentication
CVE-2023-33237 is a high-severity improper authentication vulnerability in TN-5900 Series from Moxa, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected TN-5900 Series versions: 1.0 through 3.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.63% chance of exploitation within 30 days, higher than 51% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of TN-5900 Series you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on moxa.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Moxa | TN-5900 Series | 1.0 through 3.3 | Not stated |
| Moxa | tn-5900 | 1.0 through 3.3 | Not stated |
| Moxa | Tn-5900 Firmware | 3.3 and earlier | Not stated |
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
- LowA basic user account is enough.
- 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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.8 | High | CNA (moxa.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
TN-5900 Series firmware version v3.3 and prior is vulnerable to improper-authentication vulnerability. This vulnerability arises from inadequate authentication measures implemented in the web API handler, allowing low-privileged APIs to execute restricted actions that only high-privileged APIs are allowed This presents a potential risk of unauthorized exploitation by malicious actors.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in TN-5900 Series
- 8.1 High severity
- 8.1 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
Recent Improper Authentication vulnerabilities
- 9.8 Critical severity
- 8.3 High severity
- 7.5 High severity
- 9.1 Critical severity
- 9.8 Critical severity
- 9.1 Critical severity
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