Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c41d5bc8742433d…

MALICIOUS

PDF

76.9 KB Created: 2021-09-09 02:17:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d21badf90ff6a2271a763a193b581432 SHA-1: bffb53dab5b0ee1a5af37cb6b90213405790abef SHA-256: 3c41d5bc8742433dbec158657f39f5f27c0b67e1a3c93285d52ddd88508638e0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ifa-astrologie.de/userfiles/file/34795417358.pdf In PDF document text
    • https://samsungklimamodelleri.com/upload/ckfinder/files/figezumenarigoxe.pdfIn PDF document text
    • https://drnanemilk.com/tctt/sites/aaa/file/74449493182.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613918984972e---bisetapufemawupatisopijuf.pdfIn PDF document text
    • http://rkenterprisesonline.com/FCKeditor/file/47947239749.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343a6b6a625---juneliwop.pdfIn PDF document text
    • http://akwarella.pl/user_uploads/file/zaloguzewomixorevasese.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/65150045190.pdfIn PDF document text
    • http://andreuma.madteam.net/ckfinder/userfiles/files/bivokak.pdfIn PDF document text
    • http://aluminial.pnh.pt/js/ckfinder/userfiles/files/51819551484.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/dipaneguzetuvenofadu.pdfIn PDF document text
    • http://yulintimber.cn/d/files/19172014652.pdfIn PDF document text
    • http://uteambio.com/upload/files/62292440818.pdfIn PDF document text
    • https://partnyor.az/userfiles/file/jexigovorajajorosovoloziw.pdfIn PDF document text
    • https://curewelldiabetes.com/userfiles/file/1594507226.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/xirozomitekesikuvolapuxo.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/maligoxe.pdfIn PDF document text
    • https://rosewoodcity.org/nbloom/fckuploads/file/denivurirazeperufikupug.pdfIn PDF document text
    • http://highendschmiede.de/highendfiles/file/mexipax.pdfIn PDF document text
    • http://monthclean.com/uploads/files/202109060718238988.pdfIn PDF document text
    • http://joesservicecenternj.com/userfiles/files/noxonovovemure.pdfIn PDF document text
    • https://dianthusindustrial.com/resimler/files/komilesaxabita.pdfIn PDF document text
    • http://gursakaryahukuk.com/images/file/4473346952.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137526692d3f---47254706675.pdfIn PDF document text
    • http://studionegrelli.it/userfiles/files/79877236443.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=new+headway+intermediate+4th+edition+workbook+pdf+free+downloadPDF 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_off0000c1b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1B6 11080 bytes
SHA-256: 4219b0a80bbaba9844f2b06b822fec039a0fe384cb370a064dfc993ec4c7939d
font_01_sfnt_off0000db2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2A 19292 bytes
SHA-256: 058e10ca07b0c35d8265de9baa4adab3b5563e95b44e6815e8262601769c65cf
font_02_sfnt_off00010cbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CBE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1