Malicious PDF — malware analysis report

Static analysis result for SHA-256 acd78831a486bb53…

MALICIOUS

PDF

87.2 KB Created: 2021-07-05 06:26:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f71f9d84fc057d6cd1966533adfc96dc SHA-1: e85ef6f45fe40287d8b7e8e03a43c96c50104939 SHA-256: acd78831a486bb5361517694c1f1a7c8781d34e040728b0ce85499fb50f77c2d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised WordPress sites, suggesting a phishing or redirection scheme. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://markeishahall.com/wp-content/plugins/super-forms/uploads/php/files/90ed4ac1bbd88bfdc52471c11a1d447f/dajizidezivumofuk.pdf In PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b2cc34c675e---kamuzoridufidilig.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e22de463e4e---51819612562.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9fc1590eac---juwedubigosepopuxosa.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/43317952933.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c68bc7a1416---zoliduxinowujeku.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/lragfauf3fnkean4g4rca487p5/zusabulalekavimugofu.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/pii7im6vsva12m4uvmlsi2i8qn/liwazixuziporejoxof.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/tizaxenujavig.pdfIn PDF document text
    • http://xedaptap.net/userfiles/file/rivoxakalutaxe.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/34f9t4uoihhld030hu3de7augt/puwevuxikomofozox.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/ginefuwekidu.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/ketoliriligufaver.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/vokezunumojapivojeduk.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/bcf41e76e622490ea0c3bbe4028739fe/66830736225.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/9c595c325cd50010eae1d1d1b4a93369/femid.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160a1eb9b80979---89477504613.pdfIn PDF document text
    • http://ohappy.org/userData/board/file/takujuwov.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/aobp0nnmvpakpq622gh53718d1/rabisazopugekelimenopeva.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/0be7c393dff3b20d53a1597d86ba5662/51817818499.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609103d1605a5---finazusexepadapexate.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609209a4bd901---piledubufusox.pdfIn PDF document text
    • https://honda-otolongan.com/upload/files/kowafunonenikiwevapig.pdfIn PDF document text
    • http://aytekinpolatel.com/image/files/46044519762.pdfIn PDF document text
    • http://airsoft1.ro/files/file/89529928166.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/99529446875.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160902e3ce2401---kunus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=complete+blood+work+panelPDF 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_off0000f523.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF523 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D3A 10644 bytes
SHA-256: efb636a2470895442a91941adec549e9c2246067313c92797f6f988dfbc888c0
font_02_sfnt_off00012563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12563 16224 bytes
SHA-256: 1c43e61ec4b68c9ae23ec7925c90972df17273baf7925e338f5f5712d3988072