Improper input validation in Cisco StarOS
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-770.
Summary
A vulnerability in the egress packet processing functionality of the Cisco StarOS operating system for Cisco Aggregation Services Router (ASR) 5700 Series devices and Virtualized Packet Core (VPC) System Software could allow an unauthenticated, remote attacker to cause an interface on the device to cease forwarding packets. The device may need to be manually reloaded to clear this Interface Forwarding Denial of Service condition. The vulnerability is due to the failure to properly check that the length of a packet to transmit does not exceed the maximum supported length of the network interface card (NIC). An attacker could exploit this vulnerability by sending a crafted IP packet or a series of crafted IP fragments through an interface on the targeted device. A successful exploit could allow the attacker to cause the network interface to cease forwarding packets. This vulnerability could be triggered by either IPv4 or IPv6 network traffic. This vulnerability affects the following Cisco products when they are running the StarOS operating system and a virtual interface card is installed on the device: Aggregation Services Router (ASR) 5700 Series, Virtualized Packet Core-Distributed Instance (VPC-DI) System Software, Virtualized Packet Core-Single Instance (VPC-SI) System Software. Cisco Bug IDs: CSCvf32385.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | Cisco StarOS | Cisco StarOS | — | No fix listed | CNA |
- Cisco StarOS Vendor— Affected Cisco StarOS Fixed in — No fix listed CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:staros:21.0.v0.65819:*:*:*:*:*:*:* | 21.0.v0.65819 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:staros:21.0.v4:*:*:*:*:*:*:* | 21.0.v4 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:staros:21.1.v6:*:*:*:*:*:*:* | 21.1.v6 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:staros:21.3.1:*:*:*:*:*:*:* | 21.3.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:staros:21.4.0:*:*:*:*:*:*:* | 21.4.0 | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asr_5700:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:o:cisco:staros:21.0.v0.65819:*:*:*:*:*:*:* Versions 21.0.v0.65819 Vulnerable ·Cisco
- cpe:2.3:o:cisco:staros:21.0.v4:*:*:*:*:*:*:* Versions 21.0.v4 Vulnerable ·Cisco
- cpe:2.3:o:cisco:staros:21.1.v6:*:*:*:*:*:*:* Versions 21.1.v6 Vulnerable ·Cisco
- cpe:2.3:o:cisco:staros:21.3.1:*:*:*:*:*:*:* Versions 21.3.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:staros:21.4.0:*:*:*:*:*:*:* Versions 21.4.0 Vulnerable ·Cisco
- cpe:2.3:h:cisco:asr_5700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2018-0239
- 2026-10-03 Alias added: GHSA-fr97-4833-96q9
References
More Cisco Staros vulnerabilities
- TI-2025-23504 Erlang/OTP SSH Vulnerable to Pre-Authentication RCE KEVCVSS 3.1CRITICAL 10.0
- TI-2019-01491 Cisco StarOS Denial of Service Vulnerability CVSS 3.0HIGH 8.6
- TI-2018-00328 Improper input validation in Cisco StarOS unknown CVSS 3.0HIGH 8.6
- TI-2021-01080 Cisco StarOS IPv4 Denial of Service Vulnerability CVSS 3.1HIGH 8.6
- TI-2021-01105 Cisco StarOS Denial of Service Vulnerability CVSS 3.1HIGH 7.5
- TI-2023-06755 Insufficiently protected credentials in Cisco ASR 5000 Series Software CVSS 3.1HIGH 8.8
Sources
- CVE-2018-0239 · CVE Program
- CVE-2018-0239 · NVD
- FIRST EPSS
- GHSA-fr97-4833-96q9 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences