Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f44a8b2532cdbad…

MALICIOUS

PDF

80.8 KB Created: 2021-09-22 14:58:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8bd16fc3415fc5eee4ec3598f708449d SHA-1: ab9a549bae70a5a155cabc93048022126758d08d SHA-256: 4f44a8b2532cdbada36a8cee954baedd5dc7a1220fc9cc7c47d3d71188312043
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to direct users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://sinners-party.de/media/file/zedebodaduripobisosul.pdf In PDF document text
    • http://100gastro.cz/soubory/files/96537318302.pdfIn PDF document text
    • http://mps-india.com/userfiles/files/11985406773.pdfIn PDF document text
    • https://espiber.cl/images/uploadedimages/file/18870122858.pdfIn PDF document text
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/52614384067.pdfIn PDF document text
    • http://designbeginnings.com/upload/file/xedizovaz.pdfIn PDF document text
    • https://estduquebec.com/scripts/php/xenocode/lib/ckfinder/userfiles/files/tifugu.pdfIn PDF document text
    • http://0228339500.kad.tw/kads/ckfinder/userfiles/files/dututa.pdfIn PDF document text
    • http://massarentearchitettura.com/userfiles/files/debisuxubod.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161400b241d148---3492517441.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/e17f72401f2eb9f25277f66f81195ac5/vajukodejikipemasedox.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/77115869818.pdfIn PDF document text
    • https://groupburuemas2.com/contents/files/wotinukejavofi.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/19139353533.pdfIn PDF document text
    • http://hrt-foto.hu/_user/file/falomorapufugu.pdfIn PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/1136903150.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/22727697064.pdfIn PDF document text
    • https://ginniglobal.com/uploads/file/povuxidufujujom.pdfIn PDF document text
    • http://albachiara.info/userfiles/files/suvupuruzijuxexusade.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161422399940a5---vivanama.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/ratewijomuful.pdfIn PDF document text
    • https://webdatedepot.com/userfiles/file/3841058123.pdfIn PDF document text
    • https://maintogelonline2.org/contents/files/6703944348.pdfIn PDF document text
    • http://kleiberit.ru/files/file/tafobarobol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=peter+norvig+artificial+intelligence+pdfPDF 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_off0000d7f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7F7 10692 bytes
SHA-256: cf171f893241d7387f6dd604dd00faea736404c01178fd48fc9f14c5e3c3dbe2
font_01_sfnt_off0000f06b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF06B 17488 bytes
SHA-256: 8f7d65bf09c12fb5abf48277a57f6639e583759cbf65bf70d64f2c64e37d1eaf
font_02_sfnt_off00011d8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1