CVE-2026-18728: Integer Underflow (Wrap or Wraparound) in Red Hat Red Hat Enterprise Linux 10
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.
AI Analysis
Technical Summary
CVE-2026-18728 is an integer underflow vulnerability in the iscsiuio component of open-iscsi on Red Hat Enterprise Linux 10. The flaw occurs during IPv4 DHCP parsing, where a specially crafted IPv4/UDP DHCP reply can cause an out-of-bounds read, crashing the iscsiuio process and causing a denial of service. Exploitation requires an attacker to be on the same local network segment and iscsiuio to be configured to use IPv4 DHCP. The vulnerability is rated moderate severity with a CVSS 3.1 score of 6.5 (AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
Potential Impact
The vulnerability allows a remote attacker on the same local network segment to cause a denial of service by crashing the iscsiuio process through an out-of-bounds read triggered by a crafted DHCP reply. There is no impact on confidentiality or integrity. Exploitation requires specific network conditions and configuration, limiting broader impact.
Mitigation Recommendations
No official patch or fix is currently confirmed. To mitigate this issue, restrict network access to interfaces managed by iscsiuio. Configure firewall rules to limit DHCP/BOOTP traffic to trusted infrastructure within the local broadcast domain. Consider reconfiguring iscsiuio to use static IP addresses or alternative network configurations if feasible. Changes to network configuration may require restarting the iscsiuio service. Monitor the Red Hat advisory for updates on patch availability.
CVE-2026-18728: Integer Underflow (Wrap or Wraparound) in Red Hat Red Hat Enterprise Linux 10
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.
CVSS v3.1
Score 6.5medium
Affected software
Red Hat
Red Hat Enterprise Linux 10
Red Hat
Red Hat Enterprise Linux 9
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-18728 is an integer underflow vulnerability in the iscsiuio component of open-iscsi on Red Hat Enterprise Linux 10. The flaw occurs during IPv4 DHCP parsing, where a specially crafted IPv4/UDP DHCP reply can cause an out-of-bounds read, crashing the iscsiuio process and causing a denial of service. Exploitation requires an attacker to be on the same local network segment and iscsiuio to be configured to use IPv4 DHCP. The vulnerability is rated moderate severity with a CVSS 3.1 score of 6.5 (AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
Potential Impact
The vulnerability allows a remote attacker on the same local network segment to cause a denial of service by crashing the iscsiuio process through an out-of-bounds read triggered by a crafted DHCP reply. There is no impact on confidentiality or integrity. Exploitation requires specific network conditions and configuration, limiting broader impact.
Mitigation Recommendations
No official patch or fix is currently confirmed. To mitigate this issue, restrict network access to interfaces managed by iscsiuio. Configure firewall rules to limit DHCP/BOOTP traffic to trusted infrastructure within the local broadcast domain. Consider reconfiguring iscsiuio to use static IP addresses or alternative network configurations if feasible. Changes to network configuration may require restarting the iscsiuio service. Monitor the Red Hat advisory for updates on patch availability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- redhat
- Date Reserved
- 2026-08-03T17:55:57.114Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-18728","vendor":"Red Hat"}]
Threat ID: 6a7d3d04bf8831d5399c8e47
Added to database: 08/13/2026, 03:41:56 UTC
Last enriched: 08/13/2026, 04:00:15 UTC
Last updated: 09/25/2026, 08:44:18 UTC
Views: 65
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