Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a81033f4ea3e1b8…

MALICIOUS

PDF

77.0 KB Created: 2021-09-06 21:23:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 12ade7086a80973a9236bfc63e498dfc SHA-1: 954763bec4c8edcc4b89b1055e6400005c91b2fa SHA-256: 9a81033f4ea3e1b8251b78358952f97f039b1677a8049474470b893dd0901283
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external domains, many of which are identified as link farms pointing to potentially compromised CMS upload storage. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to lure users to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://bodybybodyology.com/ckfinder/userfiles/files/30824073362.pdf In PDF document text
    • https://optimustelecoms.com/ckfinder/userfiles/files/kuwabeviruwodejefuxadup.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/zubavexilalopaboli.pdfIn PDF document text
    • http://www.saito-ken.jp/userdata/file/75136429909.pdfIn PDF document text
    • http://balassalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/85368643928.pdfIn PDF document text
    • http://kondicionery-elektrostal.ru/upload_picture/file/molubuwu.pdfIn PDF document text
    • http://benefielddarrenfordhicksunited.com/clients/2/21/2186b72972973349411f8b90e6071e14/File/35975459518.pdfIn PDF document text
    • https://cahayamimpi1.com/contents/files/24978357455.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/7rf0mrc9ctr7fcsv9461lrg18c/fefefewonevi.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/i0tr4l9ehjben4fkac57j98nnl/70596979572.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/ptvf0og05mmakkuf6pt2tf7acl/86557234483.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16094abcf8aa60---tifuvalen.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/aqalq782ef46vg2pcfncnbs0ub/dufinobogewave.pdfIn PDF document text
    • http://haiphongcontest.com/images/files/40439134475.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae92449b87---95784846975.pdfIn PDF document text
    • https://godahoian.com/app/webroot/upload/files/bomomupozewezefag.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/30742561268.pdfIn PDF document text
    • https://stijsr.com/userfiles/file/dapejubekizadeledidafeza.pdfIn PDF document text
    • https://marugame.hk/editor_upload/file/57852413513.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160d7f746bf29b---65737337519.pdfIn PDF document text
    • http://hcvitamin.com/webroot/img/files/90587627084.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c70a6df2665---leziseboropebaxofaresesi.pdfIn PDF document text
    • https://digireg.pl/upload/21526992374.pdfIn PDF document text
    • https://aznamaste.com/ckfinder/userfiles/files/nineboninufunuxes.pdfIn PDF document text
    • https://vieclambaohiem24h.com/upload/files/vidugubu.pdfIn PDF document text
    • http://adbuilder.at/ckfinder/userfiles/files/nunafapamexozudu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=azkoyen+palma+h+manualPDF 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_off0000cae8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAE8 17068 bytes
SHA-256: 28924f7f86a6de68ea7d790ceeb958934004c1fbcbd3f7a681293083dc6c5d3e
font_01_sfnt_off0000f6bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BD 10404 bytes
SHA-256: da3ca64fac1e33e2a22b330b74a44181177bf59bfab017cf4c6fb0b839b8c4c5
font_02_sfnt_off00010e2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1