CVE-2026-18726

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.

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.

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.

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.

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.

The Open-iSCSI project is a high-performance, transport independent, multi-platform implementation of RFC3720 iSCSI.

Security Fix(es):

A stack buffer overflow vulnerability exists in the idbm_recinfo_config() function in open-iscsi (iscsi-initiator-utils). An attacker can craft a malicious SendTargets TargetName containing newline characters and oversized injected keys or values to inject extra configuration lines into persisted node records. When the record is reparsed, due to missing bounds checking, a stack buffer overflow occurs, leading to denial of service or potential memory corruption. The affected component is usr/idbm.c:idbm_recinfo_config in iscsi-initiator-utils, with attacker-controlled input reaching it through SendTargets handling in usr/discovery.c.(CVE-2026-18724)

A vulnerability was found in open-iscsi. In the ICMPv6 echo-reply path of iscsiuio, the code reuses the inbound ipv6_plen field when sizing the reply instead of clamping it to the bytes actually received. An attacker can send a crafted ICMPv6 Echo Request to trigger out-of-bounds reads and a potential one-byte out-of-bounds write, which may impact confidentiality, integrity, and availability.(CVE-2026-18725)

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.(CVE-2026-18726)

A flaw was found in open-iscsi's iscsiuio component. This vulnerability involves an integer underflow and out-of-bounds read during Dynamic Host Configuration Protocol for IPv6 (DHCPv6) packet parsing. Specifically, crafted DHCPv6 Advertise traffic with a short User Datagram Protocol (UDP) length can cause the DHCPv6 payload length to underflow. An unauthenticated attacker on an adjacent network segment can exploit this by sending specially crafted IPv6 UDP traffic while the client is in an active DHCPv6 exchange, leading to a denial of service due to a process crash or service disruption.(CVE-2026-18727)

A flaw was found in open-iscsi. An integer underflow vulnerability in the iscsiuio component, specifically during IPv4 Dynamic Host Configuration Protocol (DHCP) parsing, allows a remote attacker on the same local network segment to cause a denial of service. By sending a specially crafted IPv4/UDP DHCP reply, the attacker can trigger an out-of-bounds read, leading to the iscsiuio process crashing. This issue affects systems where iscsiuio is actively handling IPv4 DHCP traffic.(CVE-2026-18728)