Malicious PDF — malware analysis report

Static analysis result for SHA-256 914c236e74b1dc20…

MALICIOUS

PDF

74.7 KB Created: 2021-09-21 05:47:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 33c2eba1ebb410cd9a63075d8a2850b9 SHA-1: 7b3545234a90e6c69a0b76e0384d9191ba75182f SHA-256: 914c236e74b1dc20d8b75819d67b1d72e563b520bbe766c7fc224836b4d74521
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://namadagaskare.ru/ckfinder/userfiles/files/84517991131.pdf In PDF document text
    • http://mail.teleserviciomalaga.com/ckfinder/userfiles/files/15128271157.pdfIn PDF document text
    • http://ambvetesopo.eu/userfiles/files/paxokadojoseg.pdfIn PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/luvuw.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/37149945968.pdfIn PDF document text
    • http://tayles.com/uploaded/39792702192.pdfIn PDF document text
    • https://emailchopper.rockeit.com/userfiles/file/piribadadodenad.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/86560323286.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161327b7b081ef---diwuwojapevusuwuxivopi.pdfIn PDF document text
    • https://aokman-drive.com/d/files/pitokexaxi.pdfIn PDF document text
    • http://stilna-ya.com/_userfiles/file/tirovugomokubagofibinu.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/88539985914.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/161418548b08e7---dasosirapinupadofemik.pdfIn PDF document text
    • http://i-akparat.kz/ckfinder/userfiles/files/76387037007.pdfIn PDF document text
    • https://bursakaynak.net/userfiles/file/sukijabozazudalakaneg.pdfIn PDF document text
    • http://inter-travel.hu/_user/file/sefubiwokiru.pdfIn PDF document text
    • http://bmfjhjk.friend-match.com/upload/files/68539819740.pdfIn PDF document text
    • http://swatimishra.in/uploaded_files/userfiles/files/wazami.pdfIn PDF document text
    • http://baove24h.org/upload/files/sapule.pdfIn PDF document text
    • http://excitechem.com/userfiles/file/wifegoweduboniladigunu.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///11121808330.pdfIn PDF document text
    • https://jerseyshorepirates.com/userfiles/files/nilosikapesasaduje.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1972c6fc6---gesigatagefurokejez.pdfIn PDF document text
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/sokebifuguvoromugemaxaba.pdfIn PDF document text
    • https://xehowo24h.com/images/ckeditor/files/21198355859.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=9+innings+pro+baseball+2016+hack+apkPDF 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_off0000bf3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF3F 11320 bytes
SHA-256: 1c066c315a0b823b81926756385ee85420dc02c6b4c6701a28301bbbb94074cd
font_01_sfnt_off0000d98d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD98D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f19f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF19F 17024 bytes
SHA-256: d60432989dfd932a7deab2544d0c1ec2c8e5c10f6a5f9b885ac805a7d21dd758