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    "cveMetadata": {
        "cveId": "CVE-2026-18103",
        "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "state": "PUBLISHED",
        "assignerShortName": "redhat",
        "dateReserved": "2026-07-28T17:35:42.520Z",
        "datePublished": "2026-08-04T23:08:02.438Z",
        "dateUpdated": "2026-08-04T23:08:02.438Z"
    },
    "containers": {
        "cna": {
            "title": "Dhcp-server: dhcp-server: persistent denial of service due to buffer overflow via omapi",
            "metrics": [
                {
                    "other": {
                        "content": {
                            "value": "Low",
                            "namespace": "https://access.redhat.com/security/updates/classification/"
                        },
                        "type": "Red Hat severity rating"
                    }
                },
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 4.9,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "HIGH",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
                        "version": "3.1"
                    },
                    "format": "CVSS"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "A flaw was found in dhcp-server. A remote attacker with network access to the OMAPI (Open Management Application Programming Interface) port, especially if not secured with TSIG (Transaction Signature) key authentication, could send a specially crafted lease creation request. This request, containing an overly long InfiniBand MAC address, triggers a buffer overflow in the `print_hw_addr()` function. Successful exploitation leads to a persistent denial of service (DoS), causing the `dhcpd` service to crash and preventing it from restarting without manual intervention."
                }
            ],
            "affected": [
                {
                    "vendor": "Red Hat",
                    "product": "Red Hat Enterprise Linux 6",
                    "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                    "packageName": "dhcp",
                    "defaultStatus": "affected",
                    "cpes": [
                        "cpe:/o:redhat:enterprise_linux:6"
                    ]
                },
                {
                    "vendor": "Red Hat",
                    "product": "Red Hat Enterprise Linux 7",
                    "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                    "packageName": "dhcp",
                    "defaultStatus": "affected",
                    "cpes": [
                        "cpe:/o:redhat:enterprise_linux:7"
                    ]
                },
                {
                    "vendor": "Red Hat",
                    "product": "Red Hat Enterprise Linux 8",
                    "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                    "packageName": "dhcp",
                    "defaultStatus": "affected",
                    "cpes": [
                        "cpe:/o:redhat:enterprise_linux:8"
                    ]
                },
                {
                    "vendor": "Red Hat",
                    "product": "Red Hat Enterprise Linux 9",
                    "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                    "packageName": "dhcp",
                    "defaultStatus": "affected",
                    "cpes": [
                        "cpe:/o:redhat:enterprise_linux:9"
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://access.redhat.com/security/cve/CVE-2026-18103",
                    "tags": [
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                        "x_refsource_REDHAT"
                    ]
                },
                {
                    "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2508081",
                    "name": "RHBZ#2508081",
                    "tags": [
                        "issue-tracking",
                        "x_refsource_REDHAT"
                    ]
                }
            ],
            "datePublic": "2026-07-28T17:35:55.440Z",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-120",
                            "description": "Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "x_redhatCweChain": "CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')",
            "workarounds": [
                {
                    "lang": "en",
                    "value": "To mitigate this issue, secure OMAPI access by configuring TSIG key authentication to prevent unauthorized connections to the OMAPI port (7911). If the `dhcpd` service has already crashed due to this flaw, manually remove the problematic InfiniBand lease entry from `/var/lib/dhcpd/dhcpd.leases` and then restart the `dhcpd` service. Restarting the `dhcpd` service may temporarily interrupt DHCP services for clients."
                }
            ],
            "timeline": [
                {
                    "lang": "en",
                    "time": "2026-07-28T17:27:20.405Z",
                    "value": "Reported to Red Hat."
                },
                {
                    "lang": "en",
                    "time": "2026-07-28T17:35:55.440Z",
                    "value": "Made public."
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "This issue was discovered by Martin Osvald (Red Hat)."
                }
            ],
            "providerMetadata": {
                "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
                "shortName": "redhat",
                "dateUpdated": "2026-08-04T23:08:02.438Z"
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