Malicious PDF — malware analysis report

Static analysis result for SHA-256 af3905148768cb31…

MALICIOUS

PDF

88.1 KB Created: 2021-07-16 00:09:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: faa9559d16756efb8f8f17f31188dc9d SHA-1: f5b850eb3d39a5b3ead0210aa3e5cbe7f1d767a2 SHA-256: af3905148768cb313dd2136a5709f81621a5c53306e01f16f9e31af27da0e615
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm pointing to compromised CMS upload storage, suggesting a phishing or malware distribution scheme. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further support the attack pattern of luring users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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 https://zlatartopalovic.rs//files/38065327759.pdf In PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/a34face3f7c32e5bdf2731fa42391f60/jutusurumajifaga.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/64e3d64ac3ef6d0f700444ecfa5e673a/tetodapipe.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a143719fc20---91589434391.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/71374914863.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/1608878045922b---88291389684.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df05869d7e2---66838725986.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/392523c8bd8b86761639193054680d49/zizejogobivit.pdfIn PDF document text
    • https://diaochue.vn/userfiles/file/73711074904.pdfIn PDF document text
    • http://hillhouseclassof1961.com/clients/c/c9/c9b049383fb65e98d0a4dcab6c176392/File/sidogukeporijuzozoxejuvap.pdfIn PDF document text
    • https://habibitours.com/ckfinder/userfiles/files/lonadowe.pdfIn PDF document text
    • https://curvy.tw/upload/files/1759821967.pdfIn PDF document text
    • https://bobecoingatlan.com/uploads/editor/file/43450000882.pdfIn PDF document text
    • http://opakowania-loga.pl/zdjecia/fotki/file/rarataxok.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609816ffea2a2---89896874466.pdfIn PDF document text
    • http://dzbnf.com/upload/file///10105029637.pdfIn PDF document text
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/4866633903.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/gk5uikspc3gc88qrqur1q7c2u1/zakoxixebofidivevirog.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/15fc32b06bf5f53b8c5cff139668f1ba/73847411134.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/70ab46397140b177c7c81a9bf080e698/93138374787.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160da7bf382849---68249205715.pdfIn PDF document text
    • http://asahiru-ban.com/files/files/xininokepukagalamaz.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/a1f831e48153bf6277771ec34fd51339/40906107839.pdfIn PDF document text
    • https://otartufo.com/ckfinder/tartufofiles/files/xenek.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/zowuvo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+convert+pdf+to+ppt+in+phonePDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e303.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE303 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB1A 10484 bytes
SHA-256: 93ddaac3f508e0194e1da3d852e5e231ed5fb76a86be83ed0d0d74e7c44154b5
font_02_sfnt_off000112d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112D6 16512 bytes
SHA-256: d353db9f3b7dc2a4a5eca27a81bcaaf53f1ceec4da312eb046977b9acced7e24
font_03_sfnt_off00013d15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D15 16144 bytes
SHA-256: fcca37035df06e555c2991ff65faa0e8497ca6423bee408ebc46b3aef925b516