CVE-2026-18727
Full vulnerability record from the local CVENow database.
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.
Severity
MEDIUM
CVSS score
6.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-08-12 22:17:14.697000
Last modified
2026-11-05 20:17:53.763000
View original CVE JSON
{
"id": "CVE-2026-18727",
"sourceIdentifier": "[email protected]",
"published": "2026-08-12T22:17:14.697",
"lastModified": "2026-11-05T20:17:53.763",
"vulnStatus": "Analyzed",
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}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 10",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "iscsi-initiator-utils",
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"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
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"vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"attackVector": "ADJACENT_NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 2.8,
"impactScore": 3.6
}
],
"ssvcV203": [
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"version": "2.0.3"
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},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-191"
}
]
}
],
"configurations": [
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"references": [
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"source": "[email protected]",
"tags": [
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},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2462956",
"source": "[email protected]",
"tags": [
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}