youker-assistant: Improper Neutralization of Special Elements used in an OS Command
CVE-2023-2091 is a high-severity improper neutralization of special elements used in an OS command vulnerability in youker-assistant from KylinSoft, 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. There is no confirmed exploitation so far. EPSS estimates a 1.47% 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 youker-assistant you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| KylinSoft | youker-assistant | Not specified in the record | 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 | 7.8 | High | CNA (vuldb.com) |
| CVSS 3.1 | 7.8 | High | NVD |
| CVSS 2.0 | 6.8 | Medium | CNA (vuldb.com) |
Official description
A vulnerability classified as critical was found in KylinSoft youker-assistant on KylinOS. Affected by this vulnerability is the function adjust_cpufreq_scaling_governer. The manipulation leads to os command injection. It is possible to launch the attack on the local host. The exploit has been disclosed to the public and may be used. Upgrading to version 3.1.4.13 is able to address this issue. It is recommended to upgrade the affected component. The associated identifier of this vulnerability is VDB-226099.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in an OS Command
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.
How developers prevent this class of flaw
- If at all possible, use library calls rather than external processes to recreate the desired functionality.
- For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
- 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.
More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)
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
Third-party and government advisories
- vuldb.com/?ctiid.226099Permissions Required, Third Party Advisory
- vuldb.com/?id.226099Third Party Advisory
Technical write-ups (may include proof of concept)
- github.com/i900008/vulndb/blob/main/youker-assistant_vuln.mdExploit, Third Party Advisory
Other references
Other vulnerabilities in youker-assistant
- 7.1 High severity
- 7.8 High severity
Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
- 8.8 High severity
- 7.8 High severity
- 7.2 High severity
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