Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f91b87cc2b318f4…

MALICIOUS

PDF

129.1 KB Created: 2021-10-14 22:13:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d43610e20b4f93ce0ae316d8463b46d5 SHA-1: 5af6ae3337a4d03806e8f40f1e26e59c0723b207 SHA-256: 8f91b87cc2b318f4ed90533281e316784a9c7713670a5c9ef116169567e0e4d8
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many of which point to compromised websites or disposable hosting, suggesting a phishing or malicious redirection attempt. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or delivering a secondary payload. No scripts were extracted, but the structure and link farm behavior are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.confirmedtour.com/files/somogolomowofekikona.pdf In PDF document text
    • https://bevasilicones.in/userfiles/file/35513463481.pdfIn PDF document text
    • https://marmetal.cevhertemizlik.com/userfiles/files/mefujimarubise.pdfIn PDF document text
    • http://awfiowv.love-mrt.com/upload/files/32300657304.pdfIn PDF document text
    • http://webs123.com/userfiles/file/21581097867.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/vqp7jvqjpevclnnbv4crmipool/gariguwodu.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/uke0r868qecj8aroe2tjtg17o0/96806632363.pdfIn PDF document text
    • http://africahistory.net/africahistory/upload/files/23257181070.pdfIn PDF document text
    • https://atarentacarburdur.com/userfiles/file/7034522642.pdfIn PDF document text
    • http://dentish.ru/ckfinder/userfiles/files/rosakojototututadog.pdfIn PDF document text
    • https://verner.lt/images/files/poligaromixoneberuwufove.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/voxowokamufukuporizuvafu.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/pufafexisal.pdfIn PDF document text
    • http://35ju.21tg.cn/uploadfile/ckeditor/files/76344565225.pdfIn PDF document text
    • http://agapetown.net/ckfinder/userfiles/files/75826471468.pdfIn PDF document text
    • http://e-restauracion.com/app/webroot/files/uploads/files/ledisokir.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/f818qutgt61rubabu7ltd66gl8/mesozitenafufusijobadixe.pdfIn PDF document text
    • http://londonjip.com/userData/board/file/newino.pdfIn PDF document text
    • http://kzlo.pl/fotki/fotki/file/rurodunumazudawivi.pdfIn PDF document text
    • https://kirbas.com/img/uploaded/file/bexitukonojozez.pdfIn PDF document text
    • https://bibonatura.hu/ckfinder/userfiles/files/fofulutanunupujus.pdfIn PDF document text
    • http://morakothotel.com/file_media/file_image/file/zeriw.pdfIn PDF document text
    • https://valleyrentals.com/userfiles/file/tixinotuzifaxowozinuj.pdfIn PDF document text
    • http://mundialimportweb.com/userfiles/file/80438849312.pdfIn PDF document text
    • http://preciz.com/uploads/wysiwyg/files/26689370911.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/HKUGBsJGI0E/uplcv?utm_term=primary+boot+loaderPDF 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_off0001916b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1916B 20324 bytes
SHA-256: df74bf8997c0c197cced222d89bf708948dbdc619f7a36b87cf3166134f4fe18
font_01_sfnt_off0001c6e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C6E8 10392 bytes
SHA-256: 48b55c0f7cd38b9c47da62ba3123a0127ad5298dc247fee627f03cf2d5d0236c
font_02_sfnt_off0001de6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1DE6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1