Cisco Analog Telephone Adaptor (ATA) Software: Execution with Unnecessary Privileges
CVE-2024-20420 is a high-severity execution with unnecessary privileges vulnerability in Cisco Analog Telephone Adaptor (ATA) Software from Cisco, 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 Cisco Analog Telephone Adaptor (ATA) Software versions: 12.0.1 SR2; 11.1.0; 12.0.1 SR1, 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 0.36% 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
- Update Ata 191 Firmware to 12.0.2 or 11.2.5, whichever matches your release line, or a later version.
- Update Ata 192 Firmware to 11.2.5 or a later version.
- Read the advisory on sec.cloudapps.cisco.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Cisco | Cisco Analog Telephone Adaptor (ATA) Software | 12.0.1 SR2; 11.1.0; 12.0.1 SR1; 11.1.0 MSR1; 11.1.0 MSR2; 11.1.0 MSR3; 11.1.0 MSR4; 12.0.1 SR3; and 7 more ranges | Not stated |
| Cisco | Ata 191 Firmware | before 12.0.2; before 11.2.5 | 12.0.2, 11.2.5 |
| Cisco | Ata 192 Firmware | before 11.2.5 | 11.2.5 |
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
- 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 | 5.4 | Medium | CNA (cisco.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
A vulnerability in the web-based management interface of Cisco ATA 190 Series Analog Telephone Adapter firmware could allow an authenticated, remote attacker with low privileges to run commands as an Admin user. This vulnerability is due to incorrect authorization verification by the HTTP server. An attacker could exploit this vulnerability by sending a malicious request to the web-based management interface. A successful exploit could allow the attacker to run commands as the Admin user.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Execution with Unnecessary Privileges
The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.
How developers prevent this class of flaw
- Run your code using the lowest privileges that are required to accomplish the necessary tasks. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
- Identify the functionality that requires additional privileges, such as access to privileged operating system resources. Wrap and centralize this functionality if possible, and isolate the privileged code as much as possible from other code. Raise privileges as late as possible, and drop them as soon as possible to avoid CWE-271. Avoid weaknesses such as CWE-288 and CWE-420 by protecting all possible communication channels that could interact with the privileged code, such as a secondary socket that is only intended to be accessed by administrators.
- Identify the functionality that requires additional privileges, such as access to privileged operating system resources. Wrap and centralize this functionality if possible, and isolate the privileged code as much as possible from other code. Raise privileges as late as possible, and drop them as soon as possible to avoid CWE-271. Avoid weaknesses such as CWE-288 and CWE-420 by protecting all possible communication channels that could interact with the privileged code, such as a secondary socket that is only intended to be accessed by administrators.
More Execution with Unnecessary Privileges vulnerabilities (CWE-250)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in Cisco Analog Telephone Adaptor (ATA) Software
- 7.1 High severity
- 7.2 High severity
- 8.2 High severity
- 8.8 High severity
- 8.8 High severity
Recent Execution with Unnecessary Privileges vulnerabilities
- 7.8 High severity
- 9.9 Critical severity
- 9.1 Critical severity
- 9.1 Critical severity
- 8.8 High severity
- 8.8 High severity
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