Malicious PDF — malware analysis report

Static analysis result for SHA-256 40fc035fb005983a…

MALICIOUS

PDF

90.6 KB Created: 2021-06-16 20:11:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 6d37bd530d657d806766a24a0fdd8f15 SHA-1: ecaa531b1dd03f46a4baf75eb2eee18fa6d0f21a SHA-256: 40fc035fb005983a8cad1cc72e016932b427be0dabc6ccbe40baf8bbcfbb8f3d
156 Risk Score

Malware Insights

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

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and is structured as a link farm, with many links pointing to compromised WordPress upload directories. This suggests the document is designed to lure users into clicking links that could lead to further compromise or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://archism.ru/uplcv?utm_term=roomba+966+vs+965 PDF link annotation
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/ro2mg48a43uf4ekrfnuubhiims/20058702308.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c3f1624e55e---92248344345.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a23329817ac---loximezulabilus.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/rrtikak6mkj8gml4rg9q6n25tu/76135583262.pdfIn PDF document text
    • http://hutergroup.de/userfiles/file/22223126848.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b92fbca11e8---67305140354.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16073eca9a8e36---nojiv.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/74892566171299ed9bb83933b9877529/xivujozejetuleg.pdfIn PDF document text
    • https://impactcleaningserviceskc.com/wp-content/plugins/super-forms/uploads/php/files/2f104be356bc2a87f21ca3492d30c20b/jabowu.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084722fcad60---wufudaneresifogomovavop.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/1bc69a057b57651fd21f80f3ed19fc9a/durasevufozolaxeranolif.pdfIn PDF document text
    • http://www.reenactmentmarket.eu/images/wyswig_images/file/2861740265.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/40d34f56002f330fd99c04857cf10a86/31255347459.pdfIn PDF document text
    • http://seoulgreeter.com/userData/board/file/fimuganosisoboxagixedil.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/6648451333.pdfIn PDF document text
    • http://dgjst.com/upfile/file/foveviwuxuvukixa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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_off000125c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125C4 5344 bytes
SHA-256: 4dcf8f6022a0c6025999b1c40ce014d1fc4a3d2bae8fdbdea2785a8d98728d53
font_01_sfnt_off000137e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137E4 11120 bytes
SHA-256: d7a3ee2ef66c432e105cd2e35dbde2ebdd5348e670b13184a85987572729484d