Malicious PDF — malware analysis report

Static analysis result for SHA-256 aec72806eb2ae0b8…

MALICIOUS

PDF

90.6 KB Created: 2021-09-21 01:37:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 36edb6993e4c053359b0679f9a53971d SHA-1: c184657419d424d159da4f9c5b7c0f938160b086 SHA-256: aec72806eb2ae0b89c38f8fda66f553d41edbc1d45a407d43194f5f0836637a8
156 Risk Score

Malware Insights

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

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The document body is heavily obfuscated and appears to be generated content rather than user-readable text, reinforcing the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://ricarda-allegra.de/userfiles/file/39627827714.pdf In PDF document text
    • http://flex-link.cn/uploadfiles/files/salakiletigudexovadumuwi.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/febizupedevujibevarud.pdfIn PDF document text
    • http://xn--djr00fsyfv0o5qgy9u.net/filespath/files/20210913062357.pdfIn PDF document text
    • https://mogilew.ru/userfiles/file/94678078079.pdfIn PDF document text
    • http://ndt-ultratech.com/files/81542531602.pdfIn PDF document text
    • http://phongkhamthienhoa.org/images/files/gawidaxotofubejasuda.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/mazamogatebururosudazo.pdfIn PDF document text
    • http://df-2.de/images/daten/file/bupejimajim.pdfIn PDF document text
    • http://muasamhangmy.com/ckfinder/userfiles/files/nivota.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/94bd2fade2fe7e42ecfd9f9d8c156191/93233837500.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/hl65h9l98370cj1pmhlststge4/97306794651.pdfIn PDF document text
    • https://illustrations.noche.fr/images/files/getufewepalamawixusokisat.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210917_30FDD6B86FBD5D2E.pdfIn PDF document text
    • http://shmgec.com/Uploadfiles/files/gobigubukelawojodowe.pdfIn PDF document text
    • http://ipmarketing.net/FCKeditor/editor/filemanager/connectors/userfiles/file/japakekosox.pdfIn PDF document text
    • http://chaputlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/99945761127.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/0a3c7852cf67645db2c5bd87af13b60e/fejanuvekimosajuki.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/57704895923.pdfIn PDF document text
    • http://hanahana.vn/media/ftp/file/87076455327.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161326f42f0551---fosebifuroxagagid.pdfIn PDF document text
    • https://whereestar.com/marinarubicon/admin/file/jekexopanewe.pdfIn PDF document text
    • http://rocb-ap.org/file_media/file_image/file/42049836010.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/16133ae3633ca1---60298081894.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=demon+slayer+movie+release+canadaPDF 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_off0000f881.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF881 10616 bytes
SHA-256: 8dbf4f05ae2739b000a21ecdc7a79666f98a49bb0514422ee4b16e7a55cf622f
font_01_sfnt_off000110c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110C0 19532 bytes
SHA-256: d48e7b2b4b21f7bcca5f982c20186e247cf4339e40779e6a9805d5db9a1aa6a0
font_02_sfnt_off00014436.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14436 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1