{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-95511", "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "state": "PUBLISHED", "assignerShortName": "redhat", "dateReserved": "2026-09-22T07:58:16.551Z", "datePublished": "2026-09-22T08:35:18.354Z", "dateUpdated": "2026-09-22T13:13:29.294Z"}, "containers": {"cna": {"title": "Cups: cups-filters: cups-filters: lpadmin can escalate to root via privileged serial backend (cups2root)", "metrics": [{"other": {"content": {"value": "Important", "namespace": "https://access.redhat.com/security/updates/classification/"}, "type": "Red Hat severity rating"}}, {"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 8.2, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "HIGH", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H", "version": "3.1"}, "format": "CVSS"}], "descriptions": [{"lang": "en", "value": "A privilege escalation vulnerability was found in CUPS when used with the cups-filters serial backend. 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The cupsd_t domain may block some of the file writes used in this chain."}], "timeline": [{"lang": "en", "time": "2026-09-18T01:07:08.000Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-09-18T01:07:08.000Z", "value": "Made public."}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-09-22T10:53:33.429Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"references": [{"url": "https://github.com/v12-security/pocs/tree/main/cups/cups2root", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-22T13:09:29.372308Z", "id": "CVE-2026-95511", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-22T13:13:29.294Z"}}]}}

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{"affected": [{"affectedData": [{"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:10"], "defaultStatus": "unaffected", "packageName": "cups-filters", "product": "Red Hat Enterprise Linux 10", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:7"], "defaultStatus": "unaffected", "packageName": "cups-filters", "product": "Red Hat Enterprise Linux 7", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:8"], "defaultStatus": "unaffected", "packageName": "cups-filters", "product": "Red Hat Enterprise Linux 8", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:9"], "defaultStatus": "unaffected", "packageName": "cups-filters", "product": "Red Hat Enterprise Linux 9", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/a:redhat:hummingbird:1"], "defaultStatus": "affected", "packageName": "cups", "product": "Red Hat Hardened Images", "vendor": "Red Hat"}], "source": "secalert@redhat.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A privilege escalation vulnerability was found in CUPS when used with the cups-filters serial backend. A local user who is a member of the lpadmin group can configure a printer that uses a privileged serial backend. The CUPS scheduler does not restrict the path component of non-file device URIs, so the root-privileged backend can write attacker-controlled print data to an arbitrary file. This can be used to change security-sensitive CUPS configuration and ultimately achieve root code execution. Exploitation requires local lpadmin group membership and a serial backend binary installed with root-only permissions."}], "id": "CVE-2026-95511", "lastModified": "2026-09-22T11:17:27.250", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 8.2, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "HIGH", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.5, "impactScore": 6.0, "source": "secalert@redhat.com", "type": "Secondary"}]}, "published": "2026-09-22T09:17:06.217", "references": [{"source": "secalert@redhat.com", "url": "https://access.redhat.com/security/cve/CVE-2026-95511"}, {"source": "secalert@redhat.com", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2537749"}, {"source": "secalert@redhat.com", "url": "https://github.com/v12-security/pocs/tree/main/cups/cups2root"}], "sourceIdentifier": "secalert@redhat.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-269"}], "source": "secalert@redhat.com", "type": "Secondary"}]}

{"bugzilla": {"description": "cups: cups-filters: cups-filters: lpadmin can escalate to root via privileged serial backend (cups2root)", "id": "2537749", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2537749"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.2", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-269", "details": ["A privilege escalation vulnerability was found in CUPS when used with the cups-filters serial backend. A local user who is a member of the lpadmin group can configure a printer that uses a privileged serial backend. The CUPS scheduler does not restrict the path component of non-file device URIs, so the root-privileged backend can write attacker-controlled print data to an arbitrary file. This can be used to change security-sensitive CUPS configuration and ultimately achieve root code execution. Exploitation requires local lpadmin group membership and a serial backend binary installed with root-only permissions."], "mitigation": {"lang": "en:us", "value": "There is no complete mitigation while the serial backend remains installed as a root backend. The following steps reduce risk:\n1. If serial printers are not required, remove the serial backend package file or change its permissions so cupsd no longer runs it as root, for example: chmod 0755 /usr/lib/cups/backend/serial (path may be /usr/libexec/cups/backend/serial).\n2. Restrict lpadmin (and other SystemGroup) membership to users who are already trusted with root-equivalent access.\n3. Leave FileDevice unset or set to No in /etc/cups/cups-files.conf.\n4. Keep SELinux in enforcing mode. The cupsd_t domain may block some of the file writes used in this chain."}, "name": "CVE-2026-95511", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "cups-filters", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "cups-filters", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "cups-filters", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "cups-filters", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "cups", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-09-18T01:07:08Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-95511\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-95511\nhttps://github.com/v12-security/pocs/tree/main/cups/cups2root"], "statement": "This vulnerability is rated as Important because a local user with CUPS administrator rights (lpadmin group) can escalate to operating-system root. Exploitation is not remote and is not available to an unprivileged local user who is not in a CUPS SystemGroup. The published cups2root chain depends on a serial backend that OpenPrinting CUPS no longer builds, but Red Hat products and Fedora still ship that backend from cups-filters, installed so that cupsd runs it as root. SELinux in enforcing mode provides additional restriction on cupsd file access and may prevent some write targets, but is not treated as a complete fix. Red Hat Enterprise Linux 8, 9, and 10, and Fedora, ship cups-filters with the serial backend and are affected. Products that ship CUPS without the cups-filters serial backend are not affected by this specific chain.", "threat_severity": "Important"}

{"created": "2026-09-22T10:00:15.332520+00:00", "updated": "2026-09-22T10:00:15.332527+00:00", "vendors": []}