Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a51ae2df678a5e2…

MALICIOUS

PDF

92.6 KB Created: 2021-07-23 18:02:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 06ea714e8d2b108d2c4d703a1a7278dc SHA-1: 381c825adab41ad3560c18301df6a71d2de567cf SHA-256: 3a51ae2df678a5e2b0ad32ee290e9534bbbf43649c32c40669c791d39ee6cf08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting an attempt to distribute malicious content or phish users. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing text but containing numerous embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://bobecoingatlan.com/uploads/editor/file/wejebo.pdf In PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16093c1c8669ce---75988522069.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/99523825889.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fcb0c58222---32465073641.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/bcevkop01lajp9e82pnq0dt6ma/doxunomesabotunalupudu.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/d0c76eca77cff63da60e5fc0c21dc00f/65573419474.pdfIn PDF document text
    • https://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/16083df8dcc2c9---tawelidimulalepevuda.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/wajesorawifebu.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/cf09b1de018699e7f9036a8bdee41f0f/xerofozoferafabixuvugupo.pdfIn PDF document text
    • https://seerupit.dk/assens/file/95178771074.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/tukuzovumavawopuvafure.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/80986746348.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6f1adfe40---jaxenafenuwikuwuzuvaki.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/def7bc4f37909319c46d352281c0be16/54608261659.pdfIn PDF document text
    • http://srutimusic.org/userfiles/file/zudabawumeniluvalewezotiv.pdfIn PDF document text
    • http://mmckno2010.zkosuchdol.info/files/12258463331.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f8e0b1b78bf---36723025324.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/37564882827.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/d1083497585f4420d1ed986f1ba6f09f/38803920158.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bda2f406bd---4706143115.pdfIn PDF document text
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dfed634bdc---kugifananisupetopege.pdfIn PDF document text
    • http://sarlampa.ru/upload_picture/21555859293.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa788fadb0a---teseriterisugeju.pdfIn PDF document text
    • https://daquin-ferriere.fr/userfiles/file/pabuwew.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/5830576a6938b4e86593670b26e9b01a/befujireropimexuwezofeju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=cubase+le+ai+elements+10.5+activation+codePDF 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_off000103a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103A0 17648 bytes
SHA-256: 899ca434a6f6b9e0dd1d6684cd5b68943bb2ce99b594b16db303c2e5704137aa
font_01_sfnt_off000130cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130CC 11140 bytes
SHA-256: 68d6a8d2037d29e2b00c682535d8ddf351b67c29fa5f8424263d26ff52bb3af0
font_02_sfnt_off00014ae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1