Cisco ASR 5000 Series Software: Uncontrolled Resource Consumption
CVE-2023-20051 is a high-severity uncontrolled resource consumption vulnerability in Cisco ASR 5000 Series Software from Cisco, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 0.87% chance of exploitation within 30 days, higher than 59% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Packet Data Network Gateway to 21.28.0 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 ASR 5000 Series Software | Not specified in the record | Not stated |
| Cisco | Packet Data Network Gateway | before 21.28.0 | 21.28.0 |
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
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 5.8 | Medium | CNA (cisco.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
A vulnerability in the Vector Packet Processor (VPP) of Cisco Packet Data Network Gateway (PGW) could allow an unauthenticated, remote attacker to stop ICMP traffic from being processed over an IPsec connection. This vulnerability is due to the VPP improperly handling a malformed packet. An attacker could exploit this vulnerability by sending a malformed Encapsulating Security Payload (ESP) packet over an IPsec connection. A successful exploit could allow the attacker to stop ICMP traffic over an IPsec connection and cause a denial of service (DoS).
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.
How developers prevent this class of flaw
- Ensure that protocols have specific limits of scale placed on them.
- Ensure that all failures in resource allocation place the system into a safe posture.
More Uncontrolled Resource Consumption vulnerabilities (CWE-400)
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 ASR 5000 Series Software
- 8.8 High severity
Recent Uncontrolled Resource Consumption vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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