CVE-2026-18726: Open-iscsi: open-iscsi: denial of service in iscsiuio router advertisement parsing

Vulnerability summary

CVE-2026-18726 is a medium (CVSS 6.5) Infinite Loop vulnerability in redhat enterprise_linux. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10% of scored vulnerabilities.

Timeline

1. 12-08-2026
   PublishedVulnerability first disclosed.
2. 18-08-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in open-iscsi. This vulnerability allows a remote attacker on the same local network segment to cause a Denial of Service (DoS) in the iscsiuio daemon. By sending a specially crafted Internet Control Message Protocol version 6 (ICMPv6) Router Advertisement with a zero-length option, the attacker can trigger an infinite loop. This leads to sustained CPU usage, rendering the daemon unresponsive and impacting system availability. A secondary risk of out-of-bounds reads exists with a short IPv6 payload, though no memory corruption or data exposure has been confirmed.

• CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.