Malicious PDF — malware analysis report

Static analysis result for SHA-256 682df3943dd75835…

MALICIOUS

PDF

79.0 KB Created: 2021-06-18 15:09:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 0453d951e9f93be658db11eb7ede05c0 SHA-1: b5c7806c0cc53f4587e7ccc922d8dcc6be051c86 SHA-256: 682df3943dd75835f7a8f30a83f26ee807f029a5b3d9c3db76f146c13f7d2cf1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The document body, though heavily obfuscated, appears to be a lure related to a scientific query, likely intended to trick users into clicking the malicious links.

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://nappsa.org/userfiles/file/jefupovepujopizom.pdf In PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a16ac2acd---levuguje.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/de966a20215563526797eefa0e094193/89477281330.pdfIn PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/voxokomiloxobupo.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16074c25a64fff---rubibotikabofujefewopoxe.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160780d5273344---30773958329.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a3667330138---89638665756.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/8839302980.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/krnnbcapocqrskee8ovd8imol2/lizagomuvaxugabubenu.pdfIn PDF document text
    • https://kermiradiatoriai.lt/images/files/32480168763.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160912d6744c33---jigabomo.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082bf0b47a14---paxejobijakuf.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/30580399962.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff5ff8e0ce---57203256632.pdfIn PDF document text
    • https://arvikabc.com/images/uploadedimages/file/15754835040.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/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=what+do+you+mean+by+exothermic+and+endothermic+reaction+with+examplePDF 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
    • 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_off0000da34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA34 5552 bytes
SHA-256: 7a7b9370567f1ed97bffa76889799c10aeb4ce0790a8d2abbb9861a49a56c306
font_01_sfnt_off0000ed0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED0D 13268 bytes
SHA-256: 31b692c3d14ad154af909b842921601749098996db8a82f3d191293ea6948567
font_02_sfnt_off000118df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118DF 16188 bytes
SHA-256: 3c30073aeef70645bf6b1eb45c3870089764dd63724e27effca40afbe49eae3d