Malicious PDF — malware analysis report

Static analysis result for SHA-256 a56e498906c33884…

MALICIOUS

PDF

82.9 KB Created: 2021-06-14 22:24:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 9157c385f2df766a57ba5a4fe90e8b9b SHA-1: 513917e056b0d64ceaa5fd682f07816cd709c44c SHA-256: a56e498906c338843c8333cd7384ca56674423fb404f05780630864ddcd60445
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high probability of malicious intent. The heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress sites and potentially disposable hosting, suggesting an attempt to redirect users to phishing or malware-hosting pages. The presence of external URIs and link farm characteristics strongly supports a malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://chcial.ru/uplcv?utm_term=tlc+in+organic+chemistry PDF link annotation
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608cca9d3835c---32844604567.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/160807dd361532---nulokexelewuvotenixa.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072e2e5486eb---gifirusuboreto.pdfIn PDF document text
    • http://anandtouristcorporation.com/uploads/sikewetuvefagokaj.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/c5460429a759c3bb2ab21fae0b339b95/wibawuwaka.pdfIn PDF document text
    • http://446888.top/userfiles/file/65385503840.pdfIn PDF document text
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/d11f315c94098fc2d4a22ebd4f02c9cf/5055978871.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1606c733fe072c---woruz.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608eb08eb6af7---daxonelixibataw.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/52e5c5761aa5148667f285e5dd1afc46/82644123455.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/xewoterogub.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160801265b631d---51809302977.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/25324742870.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/e24d174a60c6625df1f007e749ce7651/44301036145.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/5bc43c3c8b707ffff48364ee448f10db/44930099606.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606deb9a7a134---vodijavenumusizon.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/11453894642.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105DC 5264 bytes
SHA-256: d5e349513e096df5362f3d70628c1773d412fa8950aa44559f4c1d8e4c070090
font_01_sfnt_off0001179e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1179E 11628 bytes
SHA-256: 18f554731e6f7086dd4b4f07e58de0a9c890b6b7f8f96a5b146e5eba12851009