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 products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | open-iscsi | 2.1.13-1 | — |
| Debian 13 | open-iscsi | No fix yet | — |
| Debian 12 | open-iscsi | 2.1.8-1+deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | open-iscsi | No fix yet | — |
| Ubuntu 26.04 LTS | open-iscsi | No fix yet | — |
| Ubuntu 24.04 LTS | open-iscsi | No fix yet | — |
| Ubuntu 22.04 LTS | open-iscsi | No fix yet | — |
| Ubuntu 20.04 LTS | open-iscsi | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | open-iscsi | No fix yet | — |
| Ubuntu Pro 18.04 LTS | open-iscsi | No fix yet | — |
| Ubuntu Pro 16.04 LTS | open-iscsi | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | open-iscsi | 2.1.13-150500.46.6.1 | SUSE-SU-2026:5224-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP5 | open-iscsi | 2.1.13-150500.46.6.1 | SUSE-SU-2026:5224-1 |
| SLE Micro 5.5 | open-iscsi | 2.1.13-150500.46.6.1 | SUSE-SU-2026:5224-1 |
| SLE HPC 15 SP5 | open-iscsi | 2.1.13-150500.46.6.1 | SUSE-SU-2026:5224-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | open-iscsi | 2.1.13-114.1 | openSUSE-SU-2026:12102-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | iscsi-initiator-utils +3 | 6.2.1.4-10.git2a8f9d8.amzn2023.0.4 | ALAS2023-2026-2120 |
| Amazon Linux 2 | iscsi-initiator-utils +2 | 6.2.0.874-7.amzn2.0.2 | ALAS2-2026-3897 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | iscsi-initiator-utils | No fix yet | — |
Advisories 4
- SUSE-SU-2026:5224-1 Security update for open-iscsi SUSE / openSUSE Security Updates · Nov 13, 2026
- openSUSE-SU-2026:12102-1 iscsiuio-0.7.8.8-114.1 on GA media SUSE / openSUSE Security Updates · Oct 11, 2026
- ALAS2-2026-3897 Important: iscsi-initiator-utils security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Aug 31, 2026
- ALAS2023-2026-2120 Important: iscsi-initiator-utils security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 31, 2026
References
- https://access.redhat.com/security/cve/CVE-2026-18728 vdb-entry
- RHBZ#2463029 issue-tracking