CVE-2026-18727 (GCVE-0-2026-18727)
Vulnerability from cvelistv5 – Published: 2026-08-12 21:13 – Updated: 2026-08-13 03:12
VLAI
EPSS
VEX
Title
Open-iscsi: open-iscsi: integer underflow in iscsiuio dhcpv6 parsing
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.
Severity
6.5 (Medium)
CWE
- CWE-191 - Integer Underflow (Wrap or Wraparound)
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-18727 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2462956 | issue-trackingx_refsource_REDHAT |
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10 |
|
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9 |
Date Public
2026-08-12 18:05
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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