Malicious PDF — malware analysis report

Static analysis result for SHA-256 76868200ece96f6d…

MALICIOUS

PDF

74.7 KB Created: 2021-06-19 16:36:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: ff9ddf25eb828872c9096aa435ec1e68 SHA-1: 304a7c0e0083ddd17955d8902403c6d1fe9797a2 SHA-256: 76868200ece96f6d97128a37c2a5424cb17d24e60e6189ef1d37b0df7a5c0323
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, but no direct instructions or executable content were found within the document itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://kfbi.ru/content/file/1638695770.pdf In PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/3a6b7410055dc87d5baa2bafc594e981/71486614423.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc776651b3---6323138223.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/cd3bbd39ca92ecde0844b4d4677df29f/76373642519.pdfIn PDF document text
    • https://www.nosolodespedidas.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a22e6b2a3---80857490335.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/9rcr1ireqngvvs2g8maoeq8ij5/tufowozazi.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984d6969f89---24399829263.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/75432753823.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/mejose.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/0f2a6d6f0115bb6d029e16763e9562ec/37556784210.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c06655a4881---jagikigozivipowaleto.pdfIn PDF document text
    • http://www.alexgis.com/siteuploads/editorimg/file/94050717591.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c682771a78b---tozulofokagekibo.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076732540329---35340655232.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/obi2rolpfcd8ob63hj54jv1bb8/dapabutobama.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f52009d94e---96409167733.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160c3b3bdc1709---xirekanenegexerar.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=nfs+payback+trainerPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dffe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFFE 5252 bytes
SHA-256: 2680ab5ba56e00781c26ece838236fd612eeb17a6f6ec5777ece19b579484c8c
font_01_sfnt_off0000f200.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF200 13044 bytes
SHA-256: 493070a20915a27f6b0fef106bd6189c329ebc7e7dfc0c75023228e5a640a981