Vulnerability · Published Aug 13, 2026 · Assigned by redhat
CVE-2026-18728Open-iscsi: open-iscsi: integer underflow in iscsiuio ipv4 dhcp parsing
Medium 6.5
In plain English
A medium-severity security flaw in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | open-iscsi | 2.1.8-1+deb12u1 | DEBIAN-CVE-2026-18728 |
| Debian:13 | open-iscsi | no fix listed | DEBIAN-CVE-2026-18728 |
| Debian:14 | open-iscsi | 2.1.13-1 | DEBIAN-CVE-2026-18728 |
| Ubuntu:22.04:LTS | open-iscsi | no fix listed | UBUNTU-CVE-2026-18728 |
| Ubuntu:24.04:LTS | open-iscsi | no fix listed | UBUNTU-CVE-2026-18728 |
| Ubuntu:26.04:LTS | open-iscsi | no fix listed | UBUNTU-CVE-2026-18728 |
| Ubuntu:26.10 | open-iscsi | no fix listed | UBUNTU-CVE-2026-18728 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
Weakness: CWE-191 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://access.redhat.com/security/cve/CVE-2026-18728 vdb-entry, x_refsource_REDHAT
- RHBZ#2463029 issue-tracking, x_refsource_REDHAT