Malicious PDF — malware analysis report

Static analysis result for SHA-256 d839486ffa722c97…

MALICIOUS

PDF

113.5 KB Created: 2021-06-19 13:11:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: a32ceaa9e7e8afe493d71732a969213c SHA-1: 05dc9c72d1982d68e4635f7883e669cfc7bc9330 SHA-256: d839486ffa722c974267243ac76b1fd8704059c93420735f2276f8330d3ddb45
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d5c3422f55---kilapif.pdf In PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16072a75c5ca96---xarafozinaxewumewalep.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ac62f590d6c---89414452863.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/34534952989496dc06f74889999dc77a/65295730769.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/95904315673.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607650824d59d---zigiwidibuk.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/vepovasutabuk.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/94ee85a845880b219b2bf69f4d61a538/zukigiveripumureguzax.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/5unoij8sje74fn8rf4c6n20000/82706383896.pdfIn PDF document text
    • http://epoxidice.ro/mm/file/14572477860.pdfIn PDF document text
    • http://tlproduct.com/userfiles/file/71162341756.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607705fa4d00f---rafeva.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/b390f55404dd79a8e428f54d08474770/zugojimafujupile.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/58576581322.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160ad401ce36ef---jemujejojuxuvobubumisajes.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e9926000e---7886172173.pdfIn PDF document text
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/682327522980103a145e64d848eea3b1/poxelusototexapokebeju.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=hulk+hogan+theme+song+mp3+downloadPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00014eb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EB2 5392 bytes
SHA-256: 4899d55a167b457f2a30492d5bc9dce3cc1dfb2a56c11ddc3147831a6e52f252
font_01_sfnt_off000160f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x160F1 13204 bytes
SHA-256: d286df620b1e6b1410a48524ff1be6cd93bf167918ee63b3c44e8da37dc9530f
font_02_sfnt_off00018d5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18D5F 17912 bytes
SHA-256: 8b970f897e4a5e1f644deef04876b3e50f4635e067e76c4a41e27a5ba0fae08d
font_03_sfnt_off0001a81c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A81C 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378