Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3ef3b160a4bcfbb…

MALICIOUS

PDF

71.4 KB Created: 2021-09-28 20:51:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 03dee4fffc34874da5b4edd46474fb7a SHA-1: b6cc53b92a12cb8517d54da12afdde8aa8bfbe17 SHA-256: a3ef3b160a4bcfbb9b4c7a14dc84c7d3cde7d20bd8c83f6c4adf98427ad9b047
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://ysmenmidwestindia.org/uploads/userfiles/file/file/xemox.pdf In PDF document text
    • http://vattucongtrinh.com/userfiles/file/69152660731.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cad4ce0859---levuwexuxunilotagabis.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/14535172737.pdfIn PDF document text
    • https://codecs.ro/images/file/25325856220.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/16148bb3fb3298---nigikadumajozovavikuxam.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/370257af200ee6401e1048e81d6ea198/54288195182.pdfIn PDF document text
    • http://m3hotels.com/userfiles/file/fiwavawonotoze.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142d9e2571a7---fevekaburogesobu.pdfIn PDF document text
    • http://buddhavehicle.com/userfiles/file/bijutijirabis.pdfIn PDF document text
    • http://cdkuys.handysociality.com/upload/files/rosam.pdfIn PDF document text
    • http://rebeccaosborne.com/uploads/93686766922.pdfIn PDF document text
    • http://infas.cz/images/wiswig/file/68170968499.pdfIn PDF document text
    • http://dienlanhtruongson.com/upload/files/sowetad.pdfIn PDF document text
    • http://mnogonomerov.ru/uploads/file/defozadefukul.pdfIn PDF document text
    • https://balarampurblock.in/ckfinder/userfiles/files/tapexukimi.pdfIn PDF document text
    • http://bestpokeya.com/uploads/files/zugumitadobavi.pdfIn PDF document text
    • http://wolfroccatiassociati.it/userfiles/files/woxox.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/74248264619.pdfIn PDF document text
    • http://ventima.ru/userfiles/file/sinisevodusulakotezagoji.pdfIn PDF document text
    • https://konyaalotaksi.com/userfiles/file/49008915728.pdfIn PDF document text
    • http://stroykap.com/application/views/stroykap/userfiles/file/rolozerosejekumufup.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/kisepifexulilojadalilusem.pdfIn PDF document text
    • http://esipro.be/userfiles/file/90202799845.pdfIn PDF document text
    • http://reversetheclocknow.com/ckfinder/userfiles/files/77482429139.pdfIn PDF document text
    • https://landbondcorten.com/attachment/file/55c7ab2d562c4215f0dae2f743506761.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+get+current+timezone+in+android+programmaticallyPDF 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_off0000b287.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB287 11040 bytes
SHA-256: 8ec5b4392e90d85ceb32a121fd964572219f76b28a587cc7835067615eb82c0e
font_01_sfnt_off0000cc07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC07 16248 bytes
SHA-256: 8a96909585c5f30cde1431a8bc1c9c24ce56a92394205df8cc1ca257bfba9c06
font_02_sfnt_off0000f575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF575 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1