CVE-2026-116264

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{"affected": [{"affectedData": [{"collectionURL": "https://cpan.org/modules", "defaultStatus": "unaffected", "modules": ["MIME::Field::ParamVal"], "packageName": "MIME-tools", "packageURL": "pkg:cpan/MIME-tools", "programFiles": ["lib/MIME/Field/ParamVal.pm"], "programRoutines": [{"name": "MIME::Field::ParamVal::parse_params"}], "repo": "https://salsa.debian.org/dskoll/mime-tools", "versions": [{"lessThan": "5.521", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "MIME::Field::ParamVal versions before 5.521 for Perl allow one invalid Content-Type parameter to hide the parameters after it, including the multipart boundary.\n\nParameter parsing stops at the first parameter whose name it cannot read, such as x:y=1 or a name containing an 8-bit byte, and drops every parameter after it. When the boundary is among them, MIME::Parser keeps the multipart body as a single undecoded part without marking the parse as ambiguous.\n\nMail readers that skip the invalid parameter still find the boundary. A remote sender can hide an attachment from a filter that relies on ambiguous_content() while the recipient's mail client shows it."}], "id": "CVE-2026-116264", "lastModified": "2026-11-05T21:18:37.670", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-116264", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-11-05T21:05:41.347076Z", "version": "2.0.3"}}]}, "published": "2026-10-28T18:17:12.797", "references": [{"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "url": "https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes"}], "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-436"}], "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "type": "Secondary"}]}

{"bugzilla": {"description": "perl-MIME-tools: perl-MIME-tools: Security filter bypass via invalid Content-Type parameter", "id": "2563061", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2563061"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "status": "draft"}, "cwe": "CWE-1286", "details": ["MIME::Field::ParamVal versions before 5.521 for Perl allow one invalid Content-Type parameter to hide the parameters after it, including the multipart boundary.\nParameter parsing stops at the first parameter whose name it cannot read, such as x:y=1 or a name containing an 8-bit byte, and drops every parameter after it. When the boundary is among them, MIME::Parser keeps the multipart body as a single undecoded part without marking the parse as ambiguous.\nMail readers that skip the invalid parameter still find the boundary. A remote sender can hide an attachment from a filter that relies on ambiguous_content() while the recipient's mail client shows it.", "A flaw was found in perl-MIME-tools. This vulnerability allows a remote attacker to bypass email security filters by sending an email with a malformed Content-Type parameter. Because the parser halts processing upon encountering an invalid parameter name, it discards subsequent parameters, including the multipart boundary, without flagging the content as ambiguous. Consequently, security scanners fail to inspect concealed attachments that downstream email clients still render to the recipient."], "name": "CVE-2026-116264", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "perl-MIME-tools", "product_name": "Red Hat Enterprise Linux 6"}], "public_date": "2026-10-28T17:31:52Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-116264\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-116264\nhttps://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,5.521)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "manual", "scores": [{"score": 100.0, "source": "manual"}]}, "product": "mime::field::paramval", "vendor": "perl"}], "created": "2026-10-28T18:30:15.304694+00:00", "updated": "2026-10-30T15:00:15.295266+00:00", "vendors": ["perl", "perl$PRODUCT$mime::field::paramval"]}