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    "cveMetadata": {
        "cveId": "CVE-2026-91191",
        "assignerOrgId": "7d14cffa-0d7d-4270-9dc0-52cabd5a23a6",
        "state": "PUBLISHED",
        "assignerShortName": "icscert",
        "dateReserved": "2026-09-17T19:24:31.384Z",
        "datePublished": "2026-09-29T21:04:52.546Z",
        "dateUpdated": "2026-09-29T21:04:52.546Z"
    },
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            "providerMetadata": {
                "orgId": "7d14cffa-0d7d-4270-9dc0-52cabd5a23a6",
                "shortName": "icscert",
                "dateUpdated": "2026-09-29T21:04:52.546Z"
            },
            "title": "Lantronix G520 Series Cellular Gateway Improper Verification of Cryptographic Signature",
            "problemTypes": [
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                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-347",
                            "description": "CWE-347",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "Lantronix",
                    "product": "G520 Series",
                    "versions": [
                        {
                            "status": "affected",
                            "version": "2.6.0.4R6 stable"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "The device's update mechanism includes conditions that allow unauthorized software packages to be accepted as authentic. During the boot process, the stock done function disables signature verification in the OPKG configuration before restoring optional packages from a writable, unsigned feed. Separately, the publicly distributed SDK contains the production private key whose corresponding public key is trusted by both stable and beta firmware builds. Either issue undermines package authenticity, and together they allow an attacker to provide packages that appear valid to the system. Even if signature enforcement is restored, the exposed production key enables an attacker to generate signatures that the device will continue to trust. An attacker who can supply a malicious package may be able to execute arbitrary code with root privileges during installation.",
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                            "value": "The device's update mechanism includes conditions that allow unauthorized software packages to be accepted as authentic. During the boot process, the stock done function disables signature verification in the OPKG configuration before restoring optional packages from a writable, unsigned feed. Separately, the publicly distributed SDK contains the production private key whose corresponding public key is trusted by both stable and beta firmware builds. Either issue undermines package authenticity, and together they allow an attacker to provide packages that appear valid to the system. Even if signature enforcement is restored, the exposed production key enables an attacker to generate signatures that the device will continue to trust. An attacker who can supply a malicious package may be able to execute arbitrary code with root privileges during installation."
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://ltrxdev.atlassian.net/wiki/spaces/LTRXTS/pages/1889828865/Latest+firmware+for+the+G520+Series+G526+G526RP+G527+G528"
                },
                {
                    "url": "https://www.lantronix.com/technical-support/security-updates/vulnerability-disclosure-policy/vulnerability-library/"
                },
                {
                    "url": "https://www.cisa.gov/news-events/ics-advisories/icsa-26-272-01"
                },
                {
                    "url": "https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-272-01.json"
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                            "lang": "en",
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                    "cvssV3_1": {
                        "version": "3.1",
                        "attackVector": "NETWORK",
                        "attackComplexity": "HIGH",
                        "privilegesRequired": "NONE",
                        "userInteraction": "REQUIRED",
                        "scope": "UNCHANGED",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "availabilityImpact": "HIGH",
                        "baseSeverity": "HIGH",
                        "baseScore": 7.5,
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
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                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "PASSIVE",
                        "vulnConfidentialityImpact": "HIGH",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "HIGH",
                        "subAvailabilityImpact": "NONE",
                        "exploitMaturity": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "valueDensity": "NOT_DEFINED",
                        "vulnerabilityResponseEffort": "NOT_DEFINED",
                        "providerUrgency": "NOT_DEFINED",
                        "version": "4.0",
                        "baseSeverity": "HIGH",
                        "baseScore": 7.7,
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
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            ],
            "solutions": [
                {
                    "lang": "en",
                    "value": "Lantronix has addressed the reported issues with release version 2.6.0.7R6 which is available on their website.\n https://ltrxdev.atlassian.net/wiki/spaces/LTRXTS/pages/1889828865/Latest+firmware+for+the+G520+Series+G526+G526RP+G527+G528 \n\n\n\n\n\n\n\nFor more information, see the Lantronix Vulnerability Library.\n https://www.lantronix.com/technical-support/security-updates/vulnerability-disclosure-policy/vulnerability-library/ \n\n\n\nFor more information or technical assistance, contact Lantronix support: Support@lantronix.com\n mailto:Support@lantronix.com",
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                            "value": "Lantronix has addressed the reported issues with release version 2.6.0.7R6 which is available on their website.<br><div><a href=\"https://ltrxdev.atlassian.net/wiki/spaces/LTRXTS/pages/1889828865/Latest+firmware+for+the+G520+Series+G526+G526RP+G527+G528\">https://ltrxdev.atlassian.net/wiki/spaces/LTRXTS/pages/1889828865/Latest+firmware+for+the+G520+Series+G526+G526RP+G527+G528</a></div><div><br></div><div>\n<p>For more information, see the Lantronix Vulnerability Library.<br><a href=\"https://www.lantronix.com/technical-support/security-updates/vulnerability-disclosure-policy/vulnerability-library/\">https://www.lantronix.com/technical-support/security-updates/vulnerability-disclosure-policy/vulnerability-library/</a></p><p>For more information or technical assistance, contact Lantronix support: Support@lantronix.com<br><a href=\"mailto:Support@lantronix.com\">mailto:Support@lantronix.com</a></p>\n\n</div>"
                        }
                    ]
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Ievgen Bondarenko reported this vulnerability to CISA.",
                    "type": "finder"
                }
            ],
            "source": {
                "advisory": "ICSA-26-272-01",
                "discovery": "EXTERNAL"
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