{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-109399", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-10-12T14:40:48.738Z", "datePublished": "2026-10-12T15:16:44.440Z", "dateUpdated": "2026-10-12T15:16:44.440Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-10-12T15:16:44.440Z" }, "datePublic": "2026-02-11T08:00:52.000Z", "title": "SWUpdate through 2026.05.1 CMS Signature Verification Bypass via Embedded Intermediates", "descriptions": [ { "lang": "en", "value": "SWUpdate through 2026.05.1 contains an improper certificate validation vulnerability in crypto/swupdate_cms_verify_openssl.c that trusts untrusted X.509 certificates embedded in CMS SignedData for chain building. Attackers holding a signing key from a sibling intermediate under the same root can embed that intermediate in the signature to install malicious updates." } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "description": "Improper Certificate Validation", "cweId": "CWE-295", "type": "CWE" } ] } ], "affected": [ { "vendor": "sbabic", "product": "swupdate", "defaultStatus": "unaffected", "versions": [ { "version": "0", "lessThanOrEqual": "2026.05.1", "status": "affected", "versionType": "custom" } ], "packageURL": "pkg:github/sbabic/swupdate", "repo": "https://github.com/sbabic/swupdate" } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:a:swupdate:swupdate:*:*:*:*:*:*:*:*", "versionEndIncluding": "2026.05.1" } ] } ] } ], "metrics": [ { "format": "CVSS", "cvssV4_0": { "version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N", "attackVector": "NETWORK", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 9.2, "baseSeverity": "CRITICAL" } }, { "format": "CVSS", "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH", "baseScore": 8.1, "baseSeverity": "HIGH" } } ], "references": [ { "url": "https://groups.google.com/g/swupdate/c/dsoMcGFnEns", "tags": [ "technical-description", "mailing-list" ], "name": "Researcher Disclosure" }, { "url": "https://github.com/sbabic/swupdate/commit/e66c5640664a31668926a24c0c84b6b6570dc0d9", "tags": [ "patch" ] }, { "url": "https://github.com/sbabic/swupdate/blob/2026.05.1/crypto/swupdate_cms_verify_openssl.c", "tags": [ "technical-description" ] }, { "url": "https://github.com/sbabic/swupdate", "tags": [ "product" ] }, { "name": "VulnCheck Advisory: SWUpdate through 2026.05.1 CMS Signature Verification Bypass via Embedded Intermediates", "tags": [ "third-party-advisory" ], "url": "https://www.vulncheck.com/advisories/swupdate-through-2026.05.1-cms-signature-verification-bypass-via-embedded-intermediates" } ], "credits": [ { "lang": "en", "value": "David Gstir (sigma star gmbh)", "type": "finder" }, { "lang": "en", "value": "Richard Weinberger (sigma star gmbh)", "type": "finder" } ], "x_generator": { "engine": "vulncheck-endgame" } } } }