Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fc737baefacdf0d…

MALICIOUS

PDF

69.8 KB Created: 2021-09-16 04:19:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2c55bd19b7e87e6daa9f2775158fa22f SHA-1: 431e7e3da076b7fe2fc9a636130215b80dc7e6a1 SHA-256: 8fc737baefacdf0d80c2ad549a57a4c14b829a10717e5d2bceaab8cb50d4083c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to numerous URLs, many of which are hosted on compromised CMS upload storage or disposable domains, suggesting an attempt to distribute malicious content or conduct phishing. The presence of embedded URLs and the nature of the heuristics indicate that the primary function is to redirect users to external, potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://kraski-chernila.ru/resources/file/wonovorameroxivafu.pdf In PDF document text
    • http://muntepa.com/userfiles/files/10443761766.pdfIn PDF document text
    • http://szerecsengyogyszertar.hu/editor_up/80067239424.pdfIn PDF document text
    • https://queensflower.nl/clientfiles/51631840280.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/2021914134786671.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/79910054499.pdfIn PDF document text
    • https://graphicart.ro/fckfiles/file/66183983213.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133895561ad1---37947095812.pdfIn PDF document text
    • http://www.tempshift.com/app/webroot/files/uploadimagesfile/16179208286.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d8a54d40aa---berujonemewakezitodomuxon.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161416fa0208b4---7828099303.pdfIn PDF document text
    • https://rachelrom.com/rescontent/file/lokejorojupomo.pdfIn PDF document text
    • https://ibexquimica.com.br/ckfinder/userfiles/files/fetofebedor.pdfIn PDF document text
    • https://socardan.com/userfiles/files/zuvorot.pdfIn PDF document text
    • https://eseninternational.com/uploads/files/kubijuxobolerasujirexime.pdfIn PDF document text
    • http://foodzipo.com/uploads/userfiles/files/kapatovilitapo.pdfIn PDF document text
    • https://pamukoglu.com/userfiles/file/98255116761.pdfIn PDF document text
    • http://www.tahi.hu/ckfinder/userfiles/files/21883761427.pdfIn PDF document text
    • http://4x4autok.hu/userfiles/files/82736133460.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161381fbd97b53---gimoduxamekozu.pdfIn PDF document text
    • https://bruceleevideos.org/images/file/gafefudufaxuparake.pdfIn PDF document text
    • http://juditphotography.com/picture/userfiles/file/56580504980.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/15f02a2592e3cdcfadba601c54fad582/naxixunumeji.pdfIn PDF document text
    • http://offerparts.com/upload/files/95197808753.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/minubafowugize.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=android+chrome+deep+link+not+workingPDF 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_off0000b3ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3AE 10792 bytes
SHA-256: 92c1275996d2415f0cd308fff16f726d252d52e1052a1ed43a79d69fb58b4642
font_01_sfnt_off0000cc22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC22 14976 bytes
SHA-256: 060128f8f0d135bd908af7f408f2c073a09d8103fc65bebd180282a62871b28a
font_02_sfnt_off0000f177.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF177 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1