Malicious PDF — malware analysis report

Static analysis result for SHA-256 52b12a126c7f17bc…

MALICIOUS

PDF

84.3 KB Created: 2021-09-04 22:06:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 605c7283d323d82528412bba5a625001 SHA-1: 9707005c3c4a1684023d1c52f17fbc07ec6a746e SHA-256: 52b12a126c7f17bcee2754c6915a3d554253871333699cb4d2e92a4ee3e6ebd0
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many of which point to websites hosted on compromised CMS platforms or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the heuristic firings clearly point to a link farm strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://saddabro.com/userfiles/file/dapapalafaja.pdf In PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/46fe00e9f1c651402e70b700535407ed/fifejopugusokerexafuze.pdfIn PDF document text
    • http://crm333.com/documentos/file/witedaxanadebavagisetu.pdfIn PDF document text
    • http://standartbio.com/fckfiles/file/dodojekolujorilozi.pdfIn PDF document text
    • http://augustaelectricalwork.com/editorData/file/65554621169.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/d65a6496509b5c0e980076a442607ef2/fidixarani.pdfIn PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/vogazelimuz.pdfIn PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/mabotikazaxisaxexigizat.pdfIn PDF document text
    • https://emenu.hu/editor_up/26788721742.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/kn1clp4mk747g6joltsk07uhi7/wuroxuxapizepiz.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609314b5652c7---15032561958.pdfIn PDF document text
    • https://kultmotor.hu/images/files/27575961352.pdfIn PDF document text
    • http://geobigoni.it/userfiles/files/90647781137.pdfIn PDF document text
    • http://praguetransfer.com/files/file/sefutiwatixaloga.pdfIn PDF document text
    • https://mavibusiness.it/file/22188804351.pdfIn PDF document text
    • https://intekcanada.com/ckfinder/userfiles/files/zeboxilabajusudu.pdfIn PDF document text
    • http://www.naturhalles.fr/fckeditor/userfiles/file/10442804133.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160c009b449656---5230828189.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/37e40c89d1d99f73642d22880d5ce211/pexudoturinutot.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160bf957eae0ac---dabavox.pdfIn PDF document text
    • http://landmanenterprises.com/clients/6/66/660ad4be7ac834282af30b44844c6003/File/fizexunitusegelinumipejog.pdfIn PDF document text
    • https://fallsplat.se/file/54386583280.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c3d4e7c53---31269887411.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/ca5a0072025a18dda3f222baca6dc414/tumekivok.pdfIn PDF document text
    • https://geneolock.com/locktactyuma/userfiles/file/39087764841.pdfIn PDF document text
    • http://www.injamal.es/nueva/ckfinder/userfiles/files/mozetotowuderowowaroze.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607b072f18f76---mejadosaretozinomida.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=ihip+sound+pods+wireless+earbuds+user+manualPDF 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_off0000e244.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE244 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA56 18560 bytes
SHA-256: f3cb92595d4416fe76097e87a6bd214be23bf7376c54151d818fcce229156ff0
font_02_sfnt_off00012ae8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AE8 10836 bytes
SHA-256: ef19c144fee1b78b07e10d4876b647663a39e4d78fe2b94412c4da23c07749b3