Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cf804f873754a31…

MALICIOUS

PDF

82.8 KB Created: 2021-09-02 11:01:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fa64065200e3eae93a237885f57c2786 SHA-1: b7270a79fae67f88467390f9c77d57c66920c5f0 SHA-256: 4cf804f873754a314ffd653c0168ade19bbade474f8c995ab74aaab4f9dde6d0
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and hosting unknown PDF files. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristics and URLs suggest a link farm designed to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/1e7cd638c518827e2b72c7733aa9293d/refigarax.pdf In PDF document text
    • https://camgloberealtor.com/userfiles/file/mugufotarorawuto.pdfIn PDF document text
    • https://cafepiolho.com/uploads/assets/64281150784.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/9b1978a44db1a1412f053c9098408235/73995280041.pdfIn PDF document text
    • http://oletrans.sk/editor_uploads/files/78959273378.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/gepowuxelusixoxexewe.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/49136e7d5f1153d872ad8b056ed11817/gajuxof.pdfIn PDF document text
    • http://cloverpark1961.com/clients/6/6a/6a73a08bb68f643008adb5efbbb44e43/File/lazaxegot.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/16103d41111827---29000941575.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/7sm783c6jgd9blq25jaq251iq5/sexupuwibebelomobixuxaga.pdfIn PDF document text
    • http://live-net.it/file/73537529379.pdfIn PDF document text
    • http://dichvugiayphep.biz/upload/ck/files/60009227313.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c74f166c0c3---50846214693.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/6t1su47ga4f0hnhbs4s9t19nkp/9715247852.pdfIn PDF document text
    • https://rajaunited.com/contents//files/setim.pdfIn PDF document text
    • http://maisondequartierdespareuses.com/userfiles/file/tevitubawuvuweb.pdfIn PDF document text
    • https://peintures-descours.fr/fichier/files/47973333800.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6ba7e5b33---56014000320.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/92e58b6588e03ce8c8c3328ac00d62b7/wunopepozop.pdfIn PDF document text
    • http://www.leasebridge.com/CKUPimg/files/69481764806.pdfIn PDF document text
    • https://jmcoverseaspvtltd.com/uploads/files/mofugomixabif.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/b76072fe657191151d56ebe613d2824f/vifiridutajagipuze.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609b12dc978e2---83002395288.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=conditional+waiver+and+release+upon+final+paymentPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/943a5c836c67e27a2599fba8ae3887b8/28934810871.pdfIn PDF document text
    • 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_off0000db6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB6D 11056 bytes
SHA-256: eb6a5e8b491d8cefb6b4866d656600a10adcae026bbeb37f1a0538f91b1a71f3
font_01_sfnt_off0000f53c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF53C 17852 bytes
SHA-256: 04e7795f3b853938534d6133de96237cf724f2cde67755c030aa5b48d77f81cf
font_02_sfnt_off0001231f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1231F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1