Malicious PDF — malware analysis report

Static analysis result for SHA-256 dad4d91f6c5061aa…

MALICIOUS

PDF

74.8 KB Created: 2021-08-03 04:14:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 00727d7b369882e6143a691925e4ef9a SHA-1: bffa6ea8839b803a6c141ba372f67c93e7bc1a17 SHA-256: dad4d91f6c5061aa9fd0039de9bd35b71126942982f49def09af8bb4490950cf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many pointing to domains that appear to be compromised or disposable, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or directing users to malicious content. No scripts were extracted, but the link farm structure is a common tactic for distributing malware or conducting phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://wcfkenzi.com/ckfinder/userfiles/files/tejitapem.pdf In PDF document text
    • http://mosjob.ru/images/file/papuxijenivuwomiluzimemox.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/bojozafaxogunirezoxom.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/fapenivutokewabo.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/4d65d53e9b943785643bb93726e82d87/wanidexameb.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160fa921adf123---72724939455.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bb7dc8a397a---85080984657.pdfIn PDF document text
    • http://kusadasidentalclinic.com/img/userfiles/files/53948811761.pdfIn PDF document text
    • http://riph.pl/userfiles/file/zesoburabukifi.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/89808918346.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/7a0525a93d0d344bfe3ca64832fff6cb/fusadavul.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/8709f0c6aa06ddc7a06af0b5576e1ded/gabusunovetimolimozosizi.pdfIn PDF document text
    • http://riversreunion.org/clients/8699/File/5473746415.pdfIn PDF document text
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/8c37ef3d1056cc51e381c44ac7bc4633/napamure.pdfIn PDF document text
    • http://enricobarraco.com/files/10216135063.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/4m3d6k23317c1a8ooc3931mtoi/dakoxupitopupugedid.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f50cdc6004a---1571728563.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609d51d952f48---sezetasisudojofo.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0aeab9df7---sowegu.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/kv4c4e6fdtgcj7qjhcl2oj4seq/fupod.pdfIn PDF document text
    • http://nm-union.ru/ckfinder/userfiles/files/262750804.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/292c453e98baf11c1892001ed0d8499c/57573585318.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/375de888ae80396ad674bb6551e7d934/11212450114.pdfIn PDF document text
    • http://www.groupementpecheduloir.com/ckfinder/userfiles/files/33919494260.pdfIn PDF document text
    • http://wangyiphk.com/userfiles/77851907738.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=solving+linear+equations+worksheet+docPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3AF 11212 bytes
SHA-256: 4f138773bbb57f5ffd85d1927092307348a19624b8793899b95880549d665ee0
font_01_sfnt_off0000dd71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF583 15488 bytes
SHA-256: f0d23605a9fd6e75487761ba77b3f5814e85f5252cf63665c742c6d8f924a54a