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TI-2026-15349 Aliases CVE-2026-18727GHSA-g663-r6hr-qmc2

Open-iscsi: open-iscsi: integer underflow in iscsiuio dhcpv6 parsing

Priority LOW 29CWE-191Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Deferred Red Hat: fix deferred

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-191 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00285 21st percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Red HatRed Hat Enterprise Linux 10——No fix listedCNA
Red HatRed Hat Enterprise Linux 9——No fix listedCNA
  • Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*9.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*10.0VulnerableRed Hat
  • cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Red Hat

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-18727
  2. 2026-10-03 Alias added: GHSA-g663-r6hr-qmc2

References

Advisory 2

  • TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-10530 Code injection in [UNKNOWN] RichFaces KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05157 GNU Bash through 4.3 processes trailing strings after function definitions in the values… KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-23530 Sudo before 1.9.17p1 allows local users to obtain root access because /etc/nsswitch.conf… KEVCVSS 3.1CRITICAL 9.3
  • TI-2021-17490 mod_proxy SSRF KEVCVSS 3.1CRITICAL 9.0
See all 1955 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences