Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9433bc2384d3696…

MALICIOUS

PDF

84.4 KB Created: 2021-09-21 10:00:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 36e22466782c31282c525513583b3640 SHA-1: 768b98df5cc381a8b9bd1f103353d047d2b7bc69 SHA-256: a9433bc2384d36963c744467a8d8a71b37b98c57992c93a0bfa645f056996c20
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a strong intent to drive traffic to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://synerhu.ru/uplcv?utm_term=vector+design+app PDF link annotation
    • http://associatedreclaimed.reclaimedoils.com/userfiles/files/tobagakodipivepunikegubar.pdfIn PDF document text
    • https://alpasol.e-giant.net/upload/files/47164797101.pdfIn PDF document text
    • http://spodne-pradlo-2bpoint.sk/UserFiles/File/raravapig.pdfIn PDF document text
    • https://citronel.com/userfiles/files/pujejirerar.pdfIn PDF document text
    • http://champagne-marc-chauvet.com/images/files/92204327838.pdfIn PDF document text
    • https://pagodatalk.com/_UploadFile/Images/file/kasefetuxunez.pdfIn PDF document text
    • https://nbc.com.vn/ckfinder/userfiles/files/4826187300.pdfIn PDF document text
    • https://next-engineering.com/userfiles/files/jedesi.pdfIn PDF document text
    • https://arab-hams.com/Ups/files/xoturovix.pdfIn PDF document text
    • https://tybistanbul.org/resimler/files/dawisovenonifudu.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/97c14d0e8d071b07aab76103c204e775/xogodajerufanag.pdfIn PDF document text
    • http://neodermclinic.com/file_media/file_image/file/jazonatixowomunizozikosu.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/94711903198.pdfIn PDF document text
    • http://wawabed.pl/uploads/userfiles/file/30718927765.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-2/20210902220423673953.pdfIn PDF document text
    • http://form4concrete.ru/pics/cont/file/32501106221.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210913_9D4E27D54E3D7007.pdfIn PDF document text
    • http://dkstores.gr/userfiles/file/97903798440.pdfIn PDF document text
    • http://nyitotthaz.hu/userfiles/files/vegadoxojefa.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/vukiduvikitikop.pdfIn PDF document text
    • https://subded.org/userfiles/file/16590076178.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613de0dc19b2c---vobevejopadab.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0e7e83976---wunaxejinokolok.pdfIn PDF document text
    • https://stonebuild.bg/f/uploads/files/fegeraneti.pdfIn PDF document text
    • https://cmfnepal.org/userfiles/files/73007876823.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/94896360637.pdfIn PDF document text
    • 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_off0000e76b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76B 10612 bytes
SHA-256: 61cc68408e1ee8f4b932ce701042150dd351cf5ddc74502346bd55d79acff28a
font_01_sfnt_off0000ff9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000117af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117AF 17164 bytes
SHA-256: f2b7a3346e2dcf8148eab232ed4d11d797b9bb46350007a9859f413f85cdd266