SoftEther VPN: Initialization of a Resource with an Insecure Default
CVE-2023-27516 is a high-severity initialization of a resource with an insecure default vulnerability in SoftEther VPN, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected SoftEther VPN versions: 4.41-9782-beta; 5.01.9674. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.53% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of SoftEther VPN you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on softether.org for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| SoftEther VPN | SoftEther VPN | 4.41-9782-beta; 5.01.9674 | Not stated |
| Softether | vpn | 4.41-9782; 5.01.9674 | 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
- LocalThe attacker needs local access or must trick a user into running something.
- 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:L/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 | 7.3 | High | CNA (cisco.com) |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
An authentication bypass vulnerability exists in the CiRpcAccepted() functionality of SoftEther VPN 4.41-9782-beta and 5.01.9674. A specially crafted network packet can lead to unauthorized access. An attacker can send a network request to trigger this vulnerability.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Initialization of a Resource with an Insecure Default
The product initializes or sets a resource with a default that is intended to be changed by the product's installer, administrator, or maintainer, but the default is not secure.
More Initialization of a Resource with an Insecure Default vulnerabilities (CWE-1188)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Technical write-ups (may include proof of concept)
- talosintelligence.com/vulnerability_reports/TALOS-2023-1754Exploit, Third Party Advisory
Other references
Other vulnerabilities in SoftEther VPN
- 7.4 High severity
- 8.1 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Recent Initialization of a Resource with an Insecure Default vulnerabilities
- 8.8 High severity
- 8.1 High severity
- 7.8 High severity
- 7.5 High severity
- 8.6 High severity
- 9.8 Critical severity
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