Cisco IOS XR Software: Incorrect Privilege Assignment
CVE-2024-20320 is a high-severity incorrect privilege assignment vulnerability in Cisco IOS XR Software from Cisco, 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 Cisco IOS XR Software versions: 7.2.1; 7.2.2; 7.3.1, 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 0.19% 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 Cisco IOS XR Software you run against the affected versions below, and install the vendor's latest release.
- 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 IOS XR Software | 7.2.1; 7.2.2; 7.3.1; 7.3.15; 7.3.2; 7.3.3; 7.3.5; 7.4.1; and 17 more ranges | Not stated |
| Cisco | ios_xr | 7.2.1; 7.2.2; 7.3.1; 7.3.15; 7.3.2; 7.3.3; 7.3.5; 7.4.1; and 17 more ranges | 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 CNA (cisco.com).
Official description
A vulnerability in the SSH client feature of Cisco IOS XR Software for Cisco 8000 Series Routers and Cisco Network Convergence System (NCS) 540 Series and 5700 Series Routers could allow an authenticated, local attacker to elevate privileges on an affected device. This vulnerability is due to insufficient validation of arguments that are included with the SSH client CLI command. An attacker with low-privileged access to an affected device could exploit this vulnerability by issuing a crafted SSH client command to the CLI. A successful exploit could allow the attacker to elevate privileges to root on the affected device.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Privilege Assignment
A product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor.
How developers prevent this class of flaw
- Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
- 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.
More Incorrect Privilege Assignment vulnerabilities (CWE-266)
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
Other vulnerabilities in Cisco IOS XR Software
- 7.5 High severity
- 8.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 8.2 High severity
- 8.6 High severity
Recent Incorrect Privilege Assignment vulnerabilities
- 7.8 High severity
- 8.6 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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