uC-FTPs: Improper Authentication
CVE-2022-41985 is a high-severity improper authentication vulnerability in uC-FTPs from Weston Embedded, 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. Affected uC-FTPs versions: v 1.98.00. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.49% chance of exploitation within 30 days, higher than 74% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of uC-FTPs 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
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Weston Embedded | uC-FTPs | v 1.98.00 | 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
- 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
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.6 | High | CNA (cisco.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
An authentication bypass vulnerability exists in the Authentication functionality of Weston Embedded uC-FTPs v 1.98.00. A specially crafted set of network packets can lead to authentication bypass and denial of service. An attacker can send a sequence of unauthenticated packets to trigger this vulnerability.
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: poc, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Technical write-ups (may include proof of concept)
- talosintelligence.com/vulnerability_reports/TALOS-2022-1680Exploit, Third Party Advisory
Other references
Other vulnerabilities in uC-FTPs
- 7.5 High severity
- 7.5 High severity
Recent Improper Authentication vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 9.1 Critical severity
- 7.8 High severity
- 7.5 High severity
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