Description
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.
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-2026-18727 vdb-entry
- RHBZ#2462956 issue-tracking