CVE-2020-3190: Cisco IOS XR Software IPsec Packet Processor Denial of Service Vulnerability

Severity: medium (CVSS 5.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-03-04 · updated 2026-06-17
Weakness: CWE-400

Description

A vulnerability in the IPsec packet processor of Cisco IOS XR Software could allow an unauthenticated remote attacker to cause a denial of service (DoS) condition for IPsec sessions to an affected device. The vulnerability is due to improper handling of packets by the IPsec packet processor. An attacker could exploit this vulnerability by sending malicious ICMP error messages to an affected device that get punted to the IPsec packet processor. A successful exploit could allow the attacker to deplete IPsec memory, resulting in all future IPsec packets to an affected device being dropped by the device. Manual intervention is required to recover from this situation.

Affected products

Cisco IOS XR Software: before 6.4.3; from 6.6.0 before 6.6.3; from 7.0.0 before 7.0.2; from 7.1.0 before 7.1.1 — fixed in 6.4.3, 6.6.3, 7.0.2, 7.1.1

How to fix

Upgrade to a fixed version: Cisco IOS XR Software 6.4.3, 6.6.3, 7.0.2, 7.1.1. Check the vendor advisory for mitigations.

References

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