CVE-2019-1869: Cisco StarOS Denial of Service Vulnerability

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-06-20 · updated 2026-06-17
Weakness: CWE-824

Description

A vulnerability in the internal packet-processing functionality of the Cisco StarOS operating system running on virtual platforms could allow an unauthenticated, remote attacker to cause an affected device to stop processing traffic, resulting in a denial of service (DoS) condition. The vulnerability is due to a logic error that may occur under specific traffic conditions. An attacker could exploit this vulnerability by sending a series of crafted packets to an affected device. A successful exploit could allow the attacker to prevent the targeted service interface from receiving any traffic, which would lead to a DoS condition on the affected interface. The device may have to be manually reloaded to recover from exploitation of this vulnerability.

Affected products

Cisco StarOS: from 21.6 before 21.6.13; from 21.6b before 21.6b.16; from 21.7 before 21.7.11; from 21.8 before 21.8.10; from 21.9 before 21.9.7; from 21.10 before 21.10.2 — fixed in 21.10.2, 21.11.1, 21.6.13, 21.6b.16, 21.7.11, 21.8.10

How to fix

Upgrade to a fixed version: Cisco StarOS 21.10.2, 21.11.1, 21.6.13, 21.6b.16. Check the vendor advisory for mitigations.

References

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