Malicious PDF — malware analysis report

Static analysis result for SHA-256 77f35a0917c04be8…

MALICIOUS

PDF

75.9 KB Created: 2021-09-17 03:04:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 468ca33bc70735375a1dfec005358255 SHA-1: 9325c682b06909f8de177e9f15131bf87772ea88 SHA-256: 77f35a0917c04be887114e5c61ec0a0d8c7e3f3b68ffaa503ea8b45d70e43910
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous links to compromised websites and disposable hosting, suggesting a link farm designed to distribute malicious content. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://insuralead.com/userfiles/file/53052094399.pdf In PDF document text
    • http://maremio.ru/admin/ckfinder/userfiles/files/xolegexepibofi.pdfIn PDF document text
    • http://medob.org/SITE/files/editor/file/50752176484.pdfIn PDF document text
    • http://nuk-amro.de/userfiles/file/vosugixerokevotif.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/28660912434.pdfIn PDF document text
    • http://kme-kme.cz/files/file/jamifenizi.pdfIn PDF document text
    • https://primer-spb.ru/files/files/valekovamitagarezuzunor.pdfIn PDF document text
    • https://mediaget.ru/userfiles/files/46033452874.pdfIn PDF document text
    • http://kirakuramen.com/uploads/files/lidiperutamegasame.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16131232fde396---zevibogewob.pdfIn PDF document text
    • http://shesob.com/file/files/25034591092.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/80021699033.pdfIn PDF document text
    • http://4els.ru/uploads/images/files/pokigiwaxakiko.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16133bf9004971---97454304.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/161403d1a67bac---26526804456.pdfIn PDF document text
    • http://naturabliskociebie.pl/userfiles/file/godef.pdfIn PDF document text
    • http://w-mill.jp/images/file/82872104988.pdfIn PDF document text
    • http://ctcinsulator.com/uploads/file/jijafilotilitarezesusanal.pdfIn PDF document text
    • https://uleiuri.ro/userfiles/file/88020297333.pdfIn PDF document text
    • http://www.css-jp.com/upfile/files/2021/09/16/radizukuza.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333361d725f---75020967938.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141f5e8b8cea---lugisorapilitugekagomejo.pdfIn PDF document text
    • http://baschin-heizung.de/meineBilderAlbertGrundschule/file/19941306025.pdfIn PDF document text
    • https://desco.scp.hr/files/wileledonurexizuxu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=best+free+android+recovery+appPDF 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_off0000c601.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC601 10800 bytes
SHA-256: 6f5792dc49248f625fc4c22ded927265998bd1bc8130bda0ad09051f5a10fe22
font_01_sfnt_off0000df1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF1D 16808 bytes
SHA-256: 238f713e68e06731f6ba356d3ef2c4b5f83db832d8ec3ded9f0f0a8b6c67680b
font_02_sfnt_off000109dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1