Cisco Unity Connection: Unrestricted Upload of File with Dangerous Type
CVE-2024-20272 is a critical-severity unrestricted upload of file with dangerous type vulnerability in Cisco Unity Connection from Cisco, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Cisco Unity Connection versions: 12.0(1)SU1; 12.0(1)SU2; 12.0(1)SU3, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.6% chance of exploitation within 30 days, higher than 76% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Unity Connection to 12.5.1.19017-4 or 14.0.1.14006-5, whichever matches your release line, or a later version.
- Read the advisory on sec.cloudapps.cisco.com for workarounds and exact fixed builds.
- 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 |
|---|---|---|---|
| Cisco | Cisco Unity Connection | 12.0(1)SU1; 12.0(1)SU2; 12.0(1)SU3; 12.0(1)SU4; 12.0(1)SU5; 12.5(1); 12.5(1)SU1; 12.5(1)SU2; and 12 more ranges | Not stated |
| Cisco | Unity Connection | before 12.5.1.19017-4; 14.0 up to, but not including, 14.0.1.14006-5 | 12.5.1.19017-4, 14.0.1.14006-5 |
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
- 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:N/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 | 9.8 | Critical | NVD |
Official description
A vulnerability in the web-based management interface of Cisco Unity Connection could allow an unauthenticated, remote attacker to upload arbitrary files to an affected system and execute commands on the underlying operating system. This vulnerability is due to a lack of authentication in a specific API and improper validation of user-supplied data. An attacker could exploit this vulnerability by uploading arbitrary files to an affected system. A successful exploit could allow the attacker to store malicious files on the system, execute arbitrary commands on the operating system, and elevate privileges to root.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Unrestricted Upload of File with Dangerous Type
The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
How developers prevent this class of flaw
- Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.
- When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
- Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically.
More Unrestricted Upload of File with Dangerous Type vulnerabilities (CWE-434)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Cisco Unity Connection
- 7.5 High severity
- 7.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 9.3 Critical severity
Recent Unrestricted Upload of File with Dangerous Type vulnerabilities
- 9.8 Critical severity
- 9.8 Critical severity
- 8.8 High severity
- 7.2 High severity
- 9.8 Critical severity
- 9.8 Critical severity
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