Malicious PDF — malware analysis report

Static analysis result for SHA-256 a235d5c959e48ea7…

MALICIOUS

PDF

82.9 KB Created: 2021-09-11 16:13:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8b274d42058d4065cd93cc5d8a5f27dc SHA-1: fc253a0357992a7e00dac74765fd7555bc7d66ce SHA-256: a235d5c959e48ea7a0b295202f0d79c7fa2ed63b010aa305967ba3f8d07c6e54
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which are hosted on compromised CMS platforms or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, but the heuristic firings and URL analysis are sufficient to classify this as a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://antoniolescio.net/userfiles/files/87167942905.pdf In PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/kogexakuliva.pdfIn PDF document text
    • https://best-of-geldanlagen.de/userfiles/file/74911803339.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021090803095073499.pdfIn PDF document text
    • http://laureysnv.be/uploads/files/pirepen.pdfIn PDF document text
    • http://keletunderground.hu/images/uploaded_pics/file/kesidivonusezufevifexuxo.pdfIn PDF document text
    • https://mongolia-volkslift.com/uploads/files/tofez.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/42487648934.pdfIn PDF document text
    • http://carneslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/14313456201.pdfIn PDF document text
    • http://harrodsrentacar.com/public_html/userfiles/file/xunamupi.pdfIn PDF document text
    • http://wingprocess.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vekekanujipanuxunegavisip.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c06983efd2---89815771916.pdfIn PDF document text
    • https://inprovitbrasil.com/ckfinder/userfiles/files/51185492957.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/30443756795.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/wovozu.pdfIn PDF document text
    • http://bociany.sk/media/file/60593342176.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f861693f3---xivum.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16138f7869d04b---kinebukosa.pdfIn PDF document text
    • https://ozanetiket.com/TasarimAcarnet/serhali/upload/files/92980219633.pdfIn PDF document text
    • http://marymo.ru/uploads/files/lodivupalapomixirex.pdfIn PDF document text
    • http://pass38.com/images/contentimages/files/87321839937.pdfIn PDF document text
    • http://perevodvnegiloifond.ru/pict/file/nodimuwudofefonem.pdfIn PDF document text
    • https://ekselantechnology.solutions/ckfinder/userfiles/files/misupisuniput.pdfIn PDF document text
    • http://gmkms.net/upfile_editor/2021/files/zutelolixixuxoj.pdfIn PDF document text
    • https://perfecthospitals.org/FCKeditor/file/pesaw.pdfIn PDF document text
    • http://syekp.gr/sites/default/files/file/12112798583.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=things+to+build+in+minecraft+housePDF 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_off0000de19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE19 17756 bytes
SHA-256: 8f1c46c9a606c38ff41a5a01424c3b8858692e3306ad68ea2e7d3d72c3e11127
font_01_sfnt_off00010c5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012473.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12473 11128 bytes
SHA-256: 18a6744c09b3621a803d436c59dcf8ce4cfd2e06452941144bd1d049347b0e81